MULTIPLEXER SYSTEM FOR AUTOMATIC METER READING

Abstract: A multiplexer system (10) for receiving data from a plurality of interrogatable data transmitters (14) coupled to a plurality of telephone lines (12) including means (27) for coupling the multiplexer system to the plurality of telephone lines, means for sending at least one distinct interrogation signal over each of the coupled telephone lines, means (22) for receiving alternating current representations for the data sent over the coupled telephone lines from each of the plurality of interrogatable data transmitters and means (22) for converting each of the alternating current representations of the data into digital representations.

Description: MULTIPLEXER SYSTEM FOR AUTOMATIC METER READING BACKGROUND OF THE INVENTION The applicant's invention is a method and apparatus for receiving information from telephone lines and more particularly a transceiver method and apparatus for receiving data from a plurality of data transmitters which are coupled to a plurality of telephone lines after interrogating the data transmitters. The applicant's invention is particularly suited to be used in an automatic utility meter reading system of the type described in co-pending application. Serial No. , filed , 1983, for AN INTERROGATABLE AUTOMATIC METER READING SYSTEM. The applicant's invention is also particularly suited to be used to interrogate and receive data from a meter interface system of the type described in co-pending application, Serial No. 06/502,201, filed June 8,1983, for METER INTERFACE UNIT FOR UTILITY METER READNG SYSTEM. There have been other systems for receiving data from telephone lines such as one described in U.S. Patent Reissue No. 26,331 to Dumont et al. Systems of the type of the Dumont invention use the telephone company's leakage testing system to call up individual meter- installations. Once a meter installation is called up, it sends the meter information over the telephone line to a central telephone office. However, systems of the type typified by the Dumont invention have several ' disadvantages which make this type of system undesirable for its intended use. First, such systems require the use of a telephone company's leakage testing system to be operable and such leakage testing systems can change, requiring an additional large investment in new equipment configured to the new leakage testing system. As well, not all telephone companies have the same type of leakage testing equipment, so that numerous configuations of the meter reading system must be devised to fit the numerous types of leakage testing equipment. Second, such systems require a power supply, powered either from the power available at the meter installation site or from battery power, for each of its meter installations. This requirement of a power supply makes such systems costly, difficult to service, and makes the systems prone to failures due to common power outages at the installation site. Third, such systems require a complex synchronous data output on the telephone line. The synchronous output requires that the meter installations send additional sync data over the telephone line. In the event that either the synchronizing data or synchronous meter data is momentarily interrupted by even a short noise pulse, which are quite common on telephone lines, the meter data will be lost. Another type of system which has been used to send data over a telephone line is found in U.S. Patent No. 3,922,490 to Pettis. The Pettis invention is a direct current system where several resistances are switched across tip and ring of the telephone line. The current drawn by the several different combinations of resistances connected to the telephone line are sensed at a central telephone office and any of several conditions are thus communicated. Typically, in systems represented by the Pettis invention, the least significant digit /__ —i O-iMrsPJ ' ' pointer of a utility meter makes or breaks a switch depending in which half of its rotation the pointer is presented located. The making or breaking of the switch causes the resistance across the telephone line to change. This change is sensed at the central office and the cumulative count of changes or transitions are totaled and the meter reading determined therefrom. Of course, the Pettis invention, being a D.C. system, does not relate at all to the applicant's invention which is an alternating current transceiver for receiving data from a plurality of telephone lines. U.S. Patent No. 4,180,709 to Cosgrove et al, owned by the assignee of this invention, also describes a system for enabling the monitoring of a plurality of resistances placed across the D.C. telephone line. As with U.S. Patent No. 3,922,490, this invention relates only to monitoring data conducted by D.C. current changes and does not relate at all to the applicant's invention which monitors A.C. signals from the telephone line. None of the art described has been able to continuously monitor each of a plurality of telephone lines with a low impedance to the A.C. data signals sent and received without risking damage to the transceiver or the telephone lines; none of the art described has been able to receive data from data transmitters which are powered from the telephone line; and, none of the art described has been able to receive A.C. data which is asynchronous. Likewise, none of the prior art systems have provisions for automatic compensation for variations in each of the line charcteristics,. None of the prior art systems include provisions fo operating to receive utility data on an unterminated telephone line. Further, none of the prior art systems are capable of commencing simultaneously with a number of closely associated pairs of telephone lines at levels adequate for reliable data communication but low enough to prevent interference. SUMMARY OF THE INVENTION The present invention is a transceiver method and apparatus for receiving data from a plurality of data transmitters which are coupled to a plurality of telephone lines after interrogation and prompting the data from the plurality of data transmitters on an • unterminated line. The present invention comprises a means for coupling the receiver device to the plurality of telephone lines; means for sending at least one distinct interrogation signal over each of the coupled telephone lines; means for receiving an alternating current representation of the data over the coupled telephone lines from each of the plurality- of data transmitters; and, means for converting each of the alternating current representations of the data into digital representations. The transceiver of the present invention may also . include means for storing at least one of the digital representations in a digital representation storage system. Also, the transceiver may include means for multiplexing each of the distinct interrogation signals from a single output line to a particular one of the plurality of telephone lines. This multiplexing means may be supplemented with a means for multiplexing the received alternating current representations from, the plurality of coupled telephone lines to a single input line. All apparatus at the subscriber's station is powered over its telephone line thereby eliminating any need for a local powersource at the subscriber's station for the system to operate. Typically, the data from the data transmitters is a series of pulses of a single audio tone and the pulses have at least two different pulse periods. The means for converting the alternating current representation into the digital representation comprises means for filtering the series of pulses of a single audio tone received at the single input line; means for deriving a series of positive voltage pulses which are proportional in pulse period duration to the pulse period duration of the series of pulses of the single audio tone; and, means for deriving a series of zero voltage transitions which are proportional in duration to the duration of the transition periods between the pulse periods of the series of pulses of the single audio tone. The transceiver may include a means for disregarding positive voltage pulses received from the telephone lines during any of the transition periods when the positive voltage pulses have a duration corresponding to a predetermined positive noise pulse period so that the positive noise pulses on the telephone lines do not destroy the ability of the converted digital representations to reflect the proportional pulse periods of the series of pulses of the single audio tone. The transceiver may similarly include means for disregarding losses in continuity of the positive voltage pulses derived from the series of pulses of the single audio tone during any of the positive voltage pulse periods when the losses in continuity of the positive *ATIO^ voltage pulses have a duration corresponding to a predetermined negative noise pulse period so that negative going noise pulses on the telephone line do not destroy the ability of the converted digital representations to reflect the proportional pulse periods of the series of pulses of the single audio tone. The transceiver's coupling to the telephone lines may include protector circuit means for continuously coupling each of the telephone lines to the transceiver which also substantially prevents damage to the transceiver caused by high voltage conditions on the telephone lines and prevents damage to the telephone lines from short circuit conditions in the transceiver. The data from the data transmitters can be utility usage data sent over a pulse width modulated single audio tone. The transceiver can convert the pulse width modulated single audio tone into a meter identification number and usage number by employing a means for determining the relative pulse periods of the series of pulses of the single audio tone; means for determining the series of pulse periods which represent a sentinal character from the relative pulse periods; means for comparing the relative pulse periods found in at least one of the distinguishable sentinal characters to the series of pulse periods of the single audio tone, and thus defining the plurality of character periods for the series of the single audio tone; means for producing digital value signals for each of the character values in the utility usage figure and meter identification figure by comparing the relative pulse periods of the series of pulses of the single audio tone during each of the character periods with a plurality of predetermined patterns of relative pulse periods corresponding to the possible digit values found in a single character period; and, means for storing at least a portion of the digital value signal in a digital value signal storage system. The data from the utility usage monitors may also be in the form of a dual tone for each digit between 0 and 9 together with framing sentinels. This can be decoded into a serial stream of digital signals with each digital signal representing one digit of the reading from the utility usage monitor. The transceiver can respond to various commands from an external digital interface device. Such commands can be for communicating stored digital value signals or stored digital representations to the external digital interface device. Also, the transceiver can respond to trouble-shooting commands which require a particular, non-default' interrogation voltage level, duration and frequency. The trouble-shooting commands may also set a particuar non-default no-response drop-out time period for any of the telephone lines. It is also possible employing this invention for the transceiver to communicate information regarding whether a non-responsive data transmitter has been made to respond or not after the change in the voltage level, duration and frequency of the interrogation signal. The subscriber station data transmitter is powered over the telephone line and does not terminate the line at any time. Therefore, the subscriber's station is fully operational to call or be called at all times and will respond to either dialing or ringing even during a period of data transmitter interrogation. The transceiver includes means for detecting each subscriber's line condition with respect not only to an OFF HOOK condition but also variations in its impedance and leakage. Responsive to the detection of change in line characteristic as to impendance and leakage, the system correspondingly adjusts the level of interrogation signals sent over the line for optimum signal level with minimum transmitted power. Responsive to detection of line impedance or leakage outside of acceptable standards, the system registers a faulty line indication. Responsive to detection of OFF HOOK condition, the system disables data transmission without interference with normal use of the telephone line. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an electrical block diagram of an automatic meter reading system for which the present invention is particularly suited; Fig. 2 is an electrical block diagram of the preferred embodiment of the present invention showing several multiplexers controlled by a computer; Figs. 3a and 3b are an electrical schematic diagram of the computer line buffer of the present invention; Figs. 4a, 4b and 4c are an electrical schematic diagram of the master line driver/receiver of the present invention; Figs. 5a and 5b are an electrical schematic diagram of the slave line driver/receiver of the present invention; Figs. 6a, 6b, 6c, 6d, 6e, 6f, 6g and 6h are an electrical schematic diagram of the portion of the multiplexer device of .the present invention excluding the processor circuit; Figs. 7a and 7b are electrical schematic diagrams of the inut circuit of the multiplexer device of the present invention; Fig. 8 is an electrical schematic diagram of the processor circuit of the multiplexer device of the present invention; Fig. 9 is a graphical representation of the process of decoding the pulse width modulated signals* from the ' meter interface devices; Figs. 10a and 10b are a graphical representation of a flow chart of the command codes from the computer to the MUX devices; Fig. 11 is an electrical block diagram of the alternate embodiment of the present invention; and Figs. 12a, 12b, 12c and 12d are layout drawings for Figs. 3a-b, Figs. 4a-c, Figs. 5a-b and Figs. 6a-h. DETAILED DESCRIPTION OF THE INVENTION The present invention is a transceiver device and method for sending out a plurality of interrogation signals over the telephone lines, and thereafter, receiving data from a plurality of interrogation signal responsive data transmitters coupled to the telephone lines. Referring to Figure 1, although the present invention may be used in numerous applications involving data communication using telephone lines, the preferred embodiment of the present invention is particularly suited for use in an automatic meter reading system 10. This automatic meter reading system 10 is of the type described in co-pending application Serial No. , filed , 1983, for AN INTERROGATABLE AUTOMATIC METER READING SYSTEM. The multiplexer system 20 of the preferred embodiment of this invention is typically located in a central office of a telephone company. In this central location, a plurality of telephone line pairs are accessable as paths for sending and receiving the plurality of meter readings. The subscriber's site telephone line 12 typically has at least one meter interface device 14 coupled to it. The meter interface devices 14 are of the type described in co-pending application Serial No. , filed , 1983, for A METER INTERFACING DEVICE FOR AN AUTOMATIC METER READING SYSTEM. Each of the meter interface devices 14, responsive to receiving a particular distinct interrgation signal from one of several multiplexer (MUX) devices 22, will send utility usage data from at least one utility monitoring device 16 over the telephone line 12 to which it is coupled. The preferred embodiment of the multiplexer system 20 of the present invention has a plurality of MUX devices 22 coupled to all of the telephone lines 12, typically after the cut-off relays 27. Each telephone line 12 typically has at least one meter interface device 14. Thus, data sent from each of the meter interface devices 14 is received by- the MUX devices 22. The received data is converted into digital signals which represent the plurality of usage figures and meter identification figures sent from the meter interface devices 14. The digital signals are typically communicated to a computer 24 which may compile billing information and/or send the digital signals directly to other computers (not shown) located at the utility company over high speed line 26. However, it must be noted that any parallel digital interfacing device may be used such as a parallel line converted teletype or even a switch box with 16 switches because each MUX device 22 is capable of deriving at least one utility meter reading in parallel digital form and communicating the reading to any parallel digital interfacing device. Low speed lines 28 may also be installed to communicate the compiled billing information or digital signals to a storage system (not shown) in the telephone company itself. The computer 24 may also have a local terminal 23 and printer 25 for local access to the computer's 24 programming. THE PREFERRED EMBODIMENT Referring to Figure 2, the preferred embodiment of the " multiplexer system 20 of the present invention typically has a computer line buffer 35 which can interface the multiplexer system 20 to a computer 24 or other parallel digital interfacing and storage device. The computer line buffer 35 typically interfaces a 16 bit plus a strobe out-going line 32 from the computer 24 and an 8 bit incoming line 34 to the computer 24. The 16 bit out-going line 32 carries control signals which, among other tasks, tell the MUX devices 22 to interrogate a particular meter interface device 14 of Fig. 1 coupled to a particular subscriber's telephone line 12. The 16 bits are broken down first into 8 MUX select bits which allow the computer 24 to access 256 different MUX devices 22. Each MUX device 22 can typically receive data from 50 double-ended telephone lines 12 or 100 single-ended telephone lines 12. An additional 7 * bits of the 16 bit signals from the computer 24 are typically used for individual telephone line select codes. The 100 telephone lines single endedly connected to each MUX device 22 can, therefore, be individually accessed and controlled by the computer 24 by selecting the proper telephone line select code in the 7 telephone line select bits. Thus, it can be seen that computer 24 can access up to 25,600 telephone lines in the preferred embodiment of the present invention using 256 MUXES 22. As well, each telephone line 12 may have a plurality of meter interface devices 14 coupled to it, and each meter interface device 14 can have a plurality of utility usage monitors 16 coupled to it. Since a plurality of distinct interrogation signals can be sent over every coupled telephone line 12, well over 100,000 individual meter readings can be read by the preferred embodiment of the multiplexer system 20 of the present invention with the same 256 MUXES 22. Since every MUX device 22 can be connected to a typical maximum of 100 telephone lines, there are 28 different telephone line select codes left which can be used as control codes to the processor circuit 120 (shown in Figure 8) of each of the MUX devices 22. The remaining 1 bit of the 16 bits sent from the computer 24 is used as a MUX reset command which will cause the software in any particular MUX device 22 to re-initialize and start its appointed rounds all over again. Since the computer 24 is typically located some distance away from the cages 80 which house the MUX devices 22, the signals to and from the computer 24 may have to travel over a relatively long distance. To prevent loss of signals and increased noise susceptability over the long distance, each of the 16 bit out-going line 32 and 8 bit incoming line 34 are amplified before entering the cable 40 and optically coupled , at its intended receiving point. The 16 bit signals plus the strobe on the 16 bit out-going line 32 are amplified and driven over 34 lines through line driver stage 37 and optically coupled in optical coupler stage 42 in the master line driver/receiver 50. The result after being optically coupled is a single 16 bit line plus a strobe line. The 8 bit lines from the slave line driver/receivers 60 are line amplified and driven over 16 lines by line driver stage 44 in the master line driver/receiver 50 and optically coupled in optical coupler stage 39 in the computer line buffer 35. Thus, the signals to and from the computer 24 are kept free from loss and noise caused by the travel over the cable 40. Typically, each cage 80 can house twenty MUX devices 22 along with a power supply 64 and slave line driver/receiver 60. The power supply 64 can be of any conventional design which will supply plus and minus 10 volts, 5 volts, 7 volts, 12 volts and 15 volts. There can be as many cages 80 as will contain up to 256 separate MUX devices 22. However, since each cage 80 shares a single I/O line 54 from the master line driver/receiver 50, in order to drive the 20 MUX devices 22 in each cage 80, the signal levels must be boosted. The boosting of the signal levels is done in each of the slave line driver/receivers 60. Typically, the buffers in the slave line driver/receivers 60 are high impedance input and low impedance output power amplifiers which can satisfactorily drive the signals to and from the twenty MUX devices 22 in each cage 80. Typically, each cage 80 has a wire-wrap section 70 which allows a standardized MUX device 22 to be installed in each position in the cage 80 and instantly acquire the necessary distinct hardwiring which tells the MUX device 22 which one it is in the overall picture of the many MUX devices 22 and tells the MUX device 22 whether it is in the single or double ended configuration. This wire-wrap section 70 allows for quick replacement of an individual MUX device 22 which is malfunctioning by allowing a standardized MUX board (not shown) to replace any of the MUX devices 22. As previously discussed, each MUX device 22. in each cage 80 can be coupled to 50 double-ended connection to telephone lines 12 or 100 single-ended connection to telephone lines 12 depending on the longitudinal balance requirements in existence -at a particular central telephone office in which the present invention is being used. The multiplexer system 20 of the present invention then offers the ability to read at least 25,600 telephone iines 12, each of which may have multiple meter interface devices 14 coupled thereto; and, each meter interface device 14 may be individually interrogated at any time by the computer 24 or other external parallel digital interfacing device. Computer Line Buffer Referring to Figs. 3a and 3b, the computer line buffer 35 is seen. The 16 bit control codes sent over the 16 bit outgoing line 32 from the computer 24 come in through jack Jl and are amplified by line drivers U2, U3, U4 and U5 and sent over the 32 lines designated as IN1-IN32. ' The strobe signal f om the computer 24 comes in through jack J2 at strobe line 46. The strobe signal is sent through multivibrator U6 and line driver U7 to cable 40 as lines IN33 and IN34. The inputted signals from the line driver stage 44 in the master line driver/receiver 50, shown in Figures 2 and 4a, 4b, 4c and 4d are received at lines OT13-OT16. These inputted signals are then optically coupled to the computer input jack J2 through dual opto-isolators U9, U10, ϋll and U12. The signals appearing on lines IN1-IN34 and OT1-OT16 are sent over cable 40, shown in Figure 2, to the master line driver/receiver 50. Alarm circuit 75 in the computer line buffer 35 is intended to warn those in a telephone company office of computer malfunctions and will either sound an alarm in the telephone office through speaker SP1 and/or a telephone company alarm at a remote location through relay RLY1. Master Line Driver/Receiver Referring to Figures 4a, 4b and 4c, the master line driver/receiver 50 is seen. The 32 data lines IN1-IN32 ' plus the strobe lines IN33 and IN34 from the computer line buffer 35 are optically coupled by opti-isolators U17-U25 and driven into 16 output lines plus the strobe line buffer OT26-OT42 through data selector/multiplexers U28-U32. The 8 input lines IN40-IN47 from the slave line driver/receivers 60 are driven on 16 lines 0T1-0T16 to the computer line buffer 35 by line drivers U26 and U27. Activity on some of the incoming and outging lines may be indicated by the LED's D3-D18 as an aid to troubleshooting. Also, test points TP8-TP17 give easy access to certain of the output lines OT34-OT42 and ground A76. The master line driver/receiver 50 is powered by a 5 volt supply through connectors A75 and ground A76. Slave Line Driver/Receiver Referring to Figs. 5a and 5b, the slave line driver/receiver 60 can be seen. The output lines OT26-OT42 are amplified through line drivers U37-U39 and sent to the MUX devices 22 in each cage 80 through output " lines OT50-OT66. Input lines IN50-IN57 from the MUX devices 22 in the cage 80 are driven by Quad AND gates U40 and U41 to the master line driver/receiver 50 over lines IN40-IN47. Activity on certain of the lines OT50-OT66 and IN50-IN57 may be seen on LED's D20-D35 through inverting amplifiers U42, U43 and U45. The MUX Device Referring to Figs. 6a, 6b, 6c, 6d, 7a and 7b, the input circuits 100 of Figs. 6a, 6b, 6c and 6d are shown in greater detail in Figs. 7a and 7b. Fig. 7a shows the input/output circuit 100 connected in the single ended configuration. The input/output circuit 100, whether it is to be connected in the single or double ended configuration, has as its objective, a continuous coupling of the MUX device 22 to the plurality of telephone lines 22, the coupling having the following haracteristics: 1) appearing as a high resistance path to D.C. current across the connected telephone line, 2) appearing as a low impedance path from the telephone line into the MUX device 22 for alternating current between about 300 Hertz and 20,000 Hertz in frequency, 3) allowing a small D.C. leakage current to pass into the MUX device 22 so that an OFF-HOOK condition of the telephone line 12 can be sensed, 4) providing a low impedance path for interrogation signals from the MUX device 22 to the telephone line 12, and 5) protecting the MUX- device 22 from damage caused by voltage spikes commonly found on telephone lines. Fig. 7 shows the telephone line 12 ring line connected to the Bl input line and central office battery line connected to a analog ground 115 which is typically connected to the MUX digital ground 105 as shown. Line Bl has a resistor which is part of resistor pack RN25a in series with a capacitor C50a. The capacitor C50a is paralleled by a discrete resistor R90a. The side of capacitor C50a which is not common with the resistor in resistor pack RN25a is connected " to a resistor in resistor pack RN25a, which, in turn, is connected to ground 105. The telephone line 12 is wired to line Bl and ground 115 preferrably past any telephone company cut-off relay 27, of Figure 1, and directly to the telephone line OMH 12 so that when the telephone line 12 becomes OFF-HOOK, the MUX device 22 is still connected to the telephone line 12. The D.C. component of the telephone line 12 sees a high resistance path between the central office battery line and the ring line (typically in excess of 1 megohm) which will not interfere with the operation of the telephone line. If, in the worst case, capacitor C51a and the entire MUX device 22 were to short to ground 105, the telephone line would still see the resistor in resistor pack RN25a which is typically of a value of 10 kilohms. The 10 kilohms value would not interfere with the telephone line's operation by pulling an OFF-HOOK condition since resistances below 6 kilohms are required to establish an OFF-HOOK condition in most telephone lines. A small amount of D.C. current will leak through the voltage dividing resistor R90a and the resistor from resistor pack RN23a. Since the typical value of resistor R90a is 1 megohm and the typical resistance of resistor from resistor pack RN23a is 100 kilohms, the voltage at their common point is approximately divided by a factor of 10. (The resistor in resistor pack RN25a is not significant enough to change the factor.) The normal ON-HOOK, non-ringing voltage between the tip and ring of the telephone line 12 is 48 volts; therefore the voltage appearing at the common point of resistor R90a and resistor pack RN23a would be in the range of 5 volts. This 5 volts will drop dramatically when the telephone line 12 becomes OFF-HOOK, and thus the OFF-HOOK condition can be sensed from this drop in voltage. Alternating current signals from the telephone line i2 in the range between about 300 Hertz and 3000 Hertz in frequency will see a 10 kilohm resistor RN25a and a low impedance drop through capacitor C50a and continue on unabated to the input of bi-directional multiplexer/demultiplexer U61 of Figure 6a. The inter rogation signal conducted f rom multiplexer/demultiplexer U61 will also see a low impedance path through capacitor C50a because the typical interrogation signal frequency is above 500 Hertz. However, the ringing signal on the telephone line which is typically 20 Hertz in frequency will see a high impedance through capacitor C50a which will effectively block the reception of the ringing signal by the multiplexer 22. Any voltage spikes appearing on the telephone line 12, whether negative going or positive going, will be conducted as an alternating current signal through capacitor C50a. To prevent damage to the MUX device 22, the back-to-back diode array U47 is used to conduct the negative or positive going spikes to the Zener diodes D40 or D41 which act to dissipate the spike before it reaches the input of multiplexer/demultiplexer U61. Each of the input lines B1-B50 and A1-A50 of Figures 6a-d, relative to digital ground 105, will connect a single discrete telephone line 12 to the multiplexer/demultiplexers U61-U73 of Fig. 6a when the telephone lines are of the single ended type. It can be seen that the novel input-output circuit 100 of the present invention has achieved a continuous link with a telephone ' line 12. without interfering with the operation of the telephone line 12 or damaging the MUX device 22. As well, a low impendance path for alteranting current signals in either diection is continuously in existance, a high resistance path for the D.C. component is continuously in existnce, and a _ OMPI _ small amount of D.C. voltage is continuously leaked to the MUX device 22 to sense an OFF-HOOK condition. Referring to Fig. 7b, the connection of a double ended telephone line 12 is seen. The tip lead is connected to input line Al and the ring lead is connected to Bl, and, the central office battery line is connected to analog ground 115. The same action of the input/output circuit 100 previously discussed is in effect with the double ended connection. The difference between the double ended connection and the single ended connection is that, in the double ended connection, two lines of the multiplexer/demultiplexers U61-U73 are used to connectthe telephone to the MUX device 22. As will be described in more detail, the multiplexer/demultiplexers U61-U7 must be told which lines to multiplex or demultiplex. In the single ended connection, the multiplexer/demultiplexers U61-U73 must be told to multiplex or demultiplex a single line, and for the double ended connection, they must be told to multiplex or demultiplex two lines for each telephone line 12 selected . Referring again to Figures 6a, 6b, 6c, 6d, 6e, 6f, 6g and 6h, the MUX device 22 with the exception of the processing circuit 120 is seen. The computer 24 of Figure 2 selects a particular MUX device 22 of the up to 256 MUX devices 22 by sending, in the 16 bit command, an 8 bit. select code. The 8 bit select code is received in the MUX device 22 through output lines OT59-OT66. The 8 bit select code is received by two 4 bit comparators U115 and U116. The comparators U115 and U116 are responsive to the high or low conditions on input lines A61-A67 which are hardwired through hardwire circuit 70 in the MUX cage 80. As can be seen, because input line A63 is hard wired high and input lines A61, A62 and A64-A67 are hard wired low, and because input line A63 corresponds to the first of the 8 bit select code, the hardwiring in hardwire circuit 70 has made this MUX device respond to the select code for 0000001 or MUX number 1. Whenever the 16 bit Q control code from the computer 24 has bit 2 high and 9 15 bits 2 -2 low, this MUX device 22 will know that it has been selected to do a particular task which is specified in the remaining of the 16 bit control code. However, it must be noted that any of the 16 bits from the control code may be used to make the MUX select and the fact that the last 8 bits of the 16 bit control code are used here for MUX select merely a matter of choice. As previously discussed the telephone lines 12 are connected to the 13 input circuits 100. The A.C. and D:C. signals conducted to and from the telephone lines 12 are mult iplexed or demultiplexed in multiplexer/demultiplexers U61-U73. The telephone line 12 to be conducted through a particular multiplexer/demultiplexer U61-U73 is chosen by the computer 24 of Fig. 2 in the preferred embodiment of the invention. The selection of which line is to be interrogated and the utility usage figure read from is done by bits 2 -2 coming into the MUX device 22 over output lines OT60-OT56 from the slave line driver/receiver 60 of Fig. 2. The line select code in the first 7 bits of the 16 bit control code is passed to the multiplexer/demultiplexers U61-U73 and data selector/multiplexers U84-U86 and decoder/multiplexer U87 through buffers U76-U83; and, thus, a particular telephone line 12 is selected. The line select code is also sent to the processor circuit 120 of Fig. 8a, 8b, 8c and 8d via input lines PB0-PB6. The , extra 28 line select codes, as previous discussed, can be used to control special functions of the processor circuit 120. The computer 24 may then access any of the telephone lines 12 which are coupled to the multiplexer system 20 by asking for the correct MUX device 22 and asking for the correct telephone line number. The computer 24 may reset the processor circuit 7 120 of Fig. 8 by issuing a high condition on bit 2 of the 16 bit control code. The reset command is passed to the processor circuit 120 via buffer U89, Schmitt trigger Ulll and U114 and inverter U119. Once a particular telephone line 12 has been chosen by the computer 24, the telephone line 12 is first interrogated with an interrogation signal which, is typically a single audio tone at one of three discrete frequencies of 500, 810 and 1270 Hertz. It is within the capability of the software in the EPROM U124 of the processor circuit 120 to cause the sending of 256 different discrete frequencies of virtually any frequency, however, it is contemplated that 99 frequencies between 320 and 3155 Hertz with each discrete being no less than 5 percent but not . greater than 10 percent higher than the next lower frequency will be satisfactory for the preferred embodiment. We have found that frequencies as high as 20KC may be used including a . broad band of frequencies well above the audible range. As the frequency increases, the system is limited in line length but for many applications, line length is not a limiting factor. The frequencies of 500, 810 and 1270 Hertz were chosen for that reason. The interrogation tone is generated in a 1 processor circuit 120 of Fig. 8 by software in the EPROM 2 U124 and sent over line CB2 to amplifier U102 of the MUX 3 device 22. Amplifier U102 amplifies the square wave 4 signal from the processor circuit 120 and zener diode D52 5 limits the swing of the resultant tone inputted to D/A 6 converted U99. The amplitude of the outputted signal 7 from the D/A converter U99 is controlled by the processor 8 circuit 120 via input lines PA4-PA7. The outputted signal 9 is then-current to voltage converted in comparator U103 10 and made to swing between -15 and +15 volts via 11 comparators U98 and U95 and transistors Q5 and Q6. 12 Depending on whether the MUX device 22 is set up 13 in the single ended or double ended configuration, either 14 Q5 and Q6 or Q5, Q6, Q7 and 08 are used to send either a 15 single line output or double line output to the 16 input/output circuit 100, respectively. 17. The MUX device 22 is wired for single or double 18 ended operation via line 110 which is typically part of 19 the hard wire circuit 70 in MUX cage 80. When line 110 20 is connected to ground 105, the MUX device 22 is 21 configured for double ended operation. If line 110 is 22 left unconnected, the MUX device 22 is in the single 23 ended configuration. 24 Depending on whether the single or double ended 25 configuration is chosen, the interrogation tone will go 26 out over line 130 or lines 132 and 130 respectively. In 27 either case, the interrogation tone is conducted to the 28 proper telephone line 12 connected to an input output 29 circuit 100 via the line selecting done by the computer 30 24. Several different interrogation tones may be 31 sequentially sent over a single telephone line 12 by 32 sending the appropriate control code from the computer 33 24. The control code must simply select the particular MUX device and the particular telephone line. The processor circuit 120 typically knows which interrogation tones to send on any given elephone line 12. It is also possible to select the interrogation tone frequency by the control codes if this feature is desired. Referring momentarily to Fig. 9, the process of receiving the signal transmitted from each of the typical meter interface devices 14 of the automatic meter reading system is shown. Typically, each of the meter interface devices 14 of Fig. 1 send a pulse width modulated, single frequency carrier which has a typical frequency of 2000 Hertz. It is important to be. able to receive the relative pulse widths of the carrier to decode the utility usage figure and meter identification number typically sent by the meter interface device 14. This is done as follows: the pulse width modulated carrier as shown is amplified and filtered in a circuit which includes U100, U101 and U107 of Figure 6e-h. After filtering the signal, any D.C. component and any frequency substantially different than 2000 Hertz is gone. Next, the pulse width modulated carrier is passed through a Schmitt trigger U108 which clips the carrier in high and low thresholds. Then, the clipped carrier is passed through a one shot U109 which converts the pulse width to positive going D.C. pulse of approximately 5 volts in magnitude. The one shot U109 will time out typically at 1.5 times the period of the clipped carrier received, however it can be seen that the relative pulse width of the pulse width modulated carrier is intact and properly represented in the positive going D.C. pulse from the one shot U109. The D.C. pulses are fed to the processor circuit 120 of Figure 8 of the MUX device 22, which via software OMPI contained in the EPROM U124 counts the pulse periods and stores the values of the pulse periods in RAM memories U122 and U123. A positive going spike 117 which appears as a D.C. pulse of data can be eliminated in the processor 120 by having the processor circuit's 120 software disregard pulse periods of certain short durations. The typical short duration period is the minimum period of the one shot U109. A spike 117 of Fig. 9 typically is of very short duration and so will cause the one shot U109 of Fig. 6g to time out at its earliest possible time. The software is then programmed to disregard positive going pulse durations 117 which are at the minimum period of the one shot U109. The same process can be done for negative going spikes 118 which create a loss of continuity condition of pulse durations of the pulse modulated carrier. If the discontinuity of any pulse widths are of the minimum period of the one shot U109, they will be disregarded and the continuity of the pulse will be accomplished. Thus, both positive and negative going spikes 117 and 118 of short duration will not be entered into the processor circuit's 120 memory devices U122 and U1234 of Fig. 8, and the relative pulse durations of the pulse width modulated carrier will be maintained. Therefore, asynchronous data can be reliably received and decoded by the preferred embodiment of the present invention. Again referring to Figures 6a, 6b, 6c, 6d, 6e, 6f, 6g and 6h, the received signals from the input circuits 100 comes in via lines 130 and 132 in the double ended configuration. In the single ended configuration, the received signal comes in on line 130. In the double ended configuration, the two lines 130 and 132 are amplified in amplifiers U91-U93. The D.C. component leaked from the input circuit 100 is conducted to comparator U106 and buffer UllO to become a maskable interrupt to the processor circuit 120 via line CB1. The output of buffer UllO may also be used to sense the number of times a particular telephone line 12 is in the OFF-HOOK condition during a predetermined period of time. This may be done in the processor circuit 120 by counting the incidences where each telephone line 12 has been found in the OFF-HOOK condition. The telephone companies have use for the rate of use figure indicated by the count of OFF-HOOK conditions on each of the telephone lines 12. The filtered and amplified alternating current signal from the pulse width modulated carrier received from a telephone line 12 is passed through Schmitt trigger U108 which clips the signal as described in the discussion under Figure 9. The clipped signal is then inputted to a one shot U109 whose output is sent to the processor circuit 120 of Fig. 8 over line PB7. The process performed on the inputted signal from the one shot U109 has been discussed in the discussion under Fig. 9; however, it must be noted that the MUX device 22 of the preferred embodiment will operate to receive the asychronous pulse width modulated data from the meter interface devices 14, but, it can be seen that the present invention can -be configured to receive data which is transmitted in any of a number of formats. The outputted utility usage figure and meter identificaton figure from the processor circuit 120 come in on lines PA0-PA7 to the two data selector/multiplexers U118 and U117. The utility usage figure and meter identification figure are sent in 8 bit parallel digital form over input lines IN50-IN57 to the slave line driver/receiver 60.. Referring to Fig. 8, the processor circuit 120 is seen. The input/output device U121 interfaces the lines CB1, CB2, CA1, CA2, PB1-P 7 and PA0-PA7 to the microprocessor device U120, the EPROM memory device U124 and RAM memory devices U122 and U123. The EPROM device contains the software which is used by the microprocessor device U120 to control the MUX device 22. The utility usage readings and meter identification figures in the form of count period values of the positive and zero pulse widths from line PB7 are stored in the RAM memory devices U122 and U123 for analysis by the microprocessor U120 under the control of software in the EPROM U124. Once the utility usage reading and meter identification figures have been decoded, their decoded values are stored in the RAM memory devices U122 and U123 until these decoded values ae sent to the computer 24 over lines PA0-PA7. The 28 unused telephone line select codes, inputted over input lines PB0-PB7, can be used to put the microprocessor U120 in special modes of operation such as a RAM self test, EPROM check sum and MUX echo. Referring to Figures 10a and 10b, a flow chart of the commands from the computer 24 to each individual MUX device 22 is seen. The computer 24 first asks for a particular MUX number (here 255) together with a command to reset the MUX device 22 which causes the MUX device 22 to echo back the number that the MUX device 22 thinks it has as its identification figure. Next, the computer 24 commands the MUX number and telephone line number which typically causes the MUX device 22 to eaho back a 26 if the telephone line is ON-HOOK and a 30 if the telephone line is OFF-HOOK. The next command seen from the computer 24 is a cal l for a MUX numbe r 0 f or which , in the preferred embod iment , there i s no such MUX num be r . I f t h e multiplexer system 20 is operating correctly, an echo of 0 will indicate that no MUX d ev ice 22 answered to a non-existant MUX number. Next, several desired functions 1 may be selected . Dur ing normal oper a t ion of the 2 multiplexer system 20 , these desired functions can be 3 allowed to go to their default conditions so along as 4 p roper read ings are outputted to the computer 24 . 5 However, if a particular telephone line 12 connected to a 6 particular MUX device 22 does not yield readings from the 7 meter interface devices 14 coupled thereto , the computer 8 24 will start taking other measures to try to get the 9 readings. 10 The first desired function would be to change the 11 ' interroation signal level in an attempt to prompt a 12 non-respons ive meter in terface device 14. When the 13 computer command code specifies that the computer 24 14 wishes to select the interrogate level , the computer 24 15 then specifies the MUX number and telephone line select 16 code 116 which is echoed back to the computer 24 from the 17 MUX device 22. Then the MUX number and control value , 18 typically values from 0 to 15 ( zero value giving the 19 highest interrogate level and the value 15 giving the 20 lowest interrogate level ) , to set the interrogation 21 signal level are sent by the computer 24. To prevent the 22 use of higher levels than are needed , the computer 24 23 will typically choose the next highest inter roga t ion 24 signal level to see if this level will prompt a response 25 from the non-responding meter interface device 14. 26 Minimum effective interrogation signal levels for 27 reliable system operation are ach ieved employing thi s 28 system . Each line has a stored interrogation 29 lead. If no respose is received from a a l ine upon 30 interrogation , the level of the interrogation signal is 31. " increased in stepped increments (up to 15 steps ) until a 32 response is received . The new level is then stored as 33 the calibration value for that line . It constitutes an indication of the line impedance. If after the full sequence no response is received, the line is indicated to be defective and that information stored in the computer ► This feature allows the interrogation signal level to be adjusted to each individual line characteristic whereby a minimum level for reliable signalling is all that is put on the line. Crosstalk possibilities are virtually eliminated and signalling power is singificantly reduced. Next, the computer 24 has the opportunity to choose the interrogation tone duration by giving the MUX device 22 the appropriate command which includes the MUX number and telephone line select code 119. If the value 7 is sent, the MUX will send a continuous interrogation signal. This is important for troubleshooting purposes since it is possible that the telephone line 12 itself may be the cause of the no response from the meter interface device 14. The duration will range from the default duration to a continuous tone. The computer 24 as the opportunity of selecting up to 255 different frequencie for the interrogation tone sent over the selected telephone line 12 by sending the MUX number and the telephone line select code 114. The no-response dropout time is the time period that the MUX device will wait after sending the interrogation signal for the data from the meter interface device 14 to be received. ' The computer 24, after setting the characteristics of the interrogation signal or defaulting, will then send the MUX number and the telephone line select code for the telephone line 12 that is wishes to be interrogated. The MUX device 22 will send the value 13 in the lower 4 bits of its response and indicate the current interrogation signal level being used by the selected telephone line 12 in the upper 4 bits. If a proper reading is received, the MUX device 22 will typically echo a value of 15 in the lower 4 bits of the echo and an indication of the level which activated the meter interface device 14 in the upper 4 bits of the echo. The characteristics of the interrogation signal which activated the non-responsive meter interface device 14 can then be stored and used the next time this particular meter interface device 14 is interrogated upon command from the computer 24. If there was no response to the interrogation signals, the MUX device 22 will typically echo a value of 11. If there was a response but the response was unreadable, the MUX device 22 will typically echo a value of 12. If there was a proper reading received by the MUX device 22 , the computer 24 then sends the MUX number and the strobe value which causes the MUX device 22 to send a single digit of the reading to the computer 24. After this one digit is received at the computer 24 , the computer 24 sends the MUX number and strobe signal again to obtain the second digi t . When 11 d ig i ts f rom the reading have been sent , the MUX device 22 will echo the value of 29 and the computer 24 will know that that is the end of the reading . If a re-read is desired the compμter 24 will re-enter to logical flow at entry point A of Figure 10a. ALTERNATE EMBODIMENT . Referring to Fig. 11, it might be desirable to receive the utility usage figure and meter identification ' - OMH figure in the form of a dual tone system. This dual tone system if of the type commonly used by telephone companies for subscriber signalling referred to in the Bell System as the touch tone dialing system. In this dual tone system, each w digit from 0 to 9 is sent over the telephone line as a distinct pair of audio tones. These distinct pairs of audio tones are easily decoded at the receiving location into the intended series of digits. The dual tone system would enable a single digit of both the utility usage figure ' and meter identification figure to be sent with a single dual tone signal since all digits from 0 to 9 are available in the dual tone system. The pound sign (#) and the star sign (*) could be used as framing sentinals for the reading from each meter interface device 14. The alternate embodiment described in co-pending application Serial No. 06/502,201, filed June 8, 1983, for METER INTERFACE UNIT FOR UTILITY METER READING SYSTEM could be used as the meter interface device 14 which will send the utility usage figure and meter identification figure to the alternate embodiment of the MUX device 22. The MUX device 22, to decode these dual tone signals, would have to be changed from the preferred embodiment only slightly. The only change necessary would be to include a DTMF receiver circuit 150, which is available commercially as an integrated circuit SSI 201, in place of the band pass filters U100, U101 and U107, Schmitt trigger U108 and one shot U109. When the individual dual tones are received and multiplexed to the DTMF receiver 150, the output from the DTMF receiver 150 is a serial digital signal indicating each digit and framing sentinels from the meter interface device 14. Instead of decoding the. relative pulse widths in the preferred embodiment , the processor 120 , in the alternate embodiment , must only store the values as an entire reading from the individual meter interface device 14. The software necessa ry or the decoding of the reltive pulse width of the preferred embod iment i s unnecessary and the speed of receiving the individual readings is, therefore, increased. Th e processor 120 may have control over the filtering done in the DTMF receiver circu i t 150 over control line 155 ; and , although the OFF-HOOK information can still be used in the alternate embod iment , the readings can now be done over the OFF-HOOK telephone line without interfering with it ' s operation. The maskable interrupt from UllO of Fig. 6f can be disregarded by the processor 120 of Fig . 8. The OFF-HOOK telephone line will not be interfered with by the sending of the dual tones for the following reasons : first, the dual tones would be chosen so that they did not coincide with the dual ones used for dialing . The SSI 201 integrated circuit used for the DTMF receiver circuit 150 requires a crystal for its time base ; the crystal need simply be changed in frequency to change the frequencies of the dual tones which will be received by the MUX device 22. - Second , in the OFF-HOOK condition , the sending of the utility usage figure and the meter identification figure would be so short that the subscr iber would not be bothered by the short bursts of tones if he happened to ' • pick up his telephone at the instant of sending the reading. Being able to interrogate the. receive readings over OFF-HOOK telephone lines will allow time of day readings which are especially useful to the electric companies. The speed of sending the dual tone digits will add to the OMPI &i?NATiO$^ 1 speed of receiving each reading and therefore to the 2 speed of the entire multiplexer system 20. 3 4 List Of Component Values For The Preferred Embodiment 5 6 The following is a listing of the component values 7 found to be satisfactory in the preferred embodiment of 8 the invention. 9 10 The computer 24 is a NOVA 3D manufactured by Data General 11 Corporation. 12 13 The following is a list of the integrated circuits 14 found to operate satisfactorily with the preferred 15 embodiment: U2-U5, U7 , U26 and U2 are MC3487P 16 manufactured by Motorola. 17 U9-U12 and U17-U25 are HCPL 2630 opto-isolators. 18 U6 is a 74L121 multivibrator. 19 U8 is a MC 14521B 24 stage frequency divider manufactured 20 by Motorola. 21 U13 is a type 555 timer. 22. U14-U16 are contained, in a single 14501. 23 U28-U32.are 74LS258A data selector/multiplexers. 24 U33 and U35 are contained in a single 75492 HEX buffer '25 manufactured by National Semiconductor. 26 U34, U36, U42 and U45 are 75492 HEX buffers manufactured 27 by National Semiconductor. 28 U43 and U44 are contained in a single 75492 HEX buffer 29 manufactured by National Semiconductor. 30 U37-U39 are 74C902 CMOS HEX non-inverting TTL buffers 31 manufactured by National Semiconductor. 32 U40 and U41 are 74LS09 quad AND gates. 33 U47-U59 are back-to-back diode arrays FSA 2510M. U61-U74 are single 8 channel analog multiplexer/demultiplexers 4051. U84-U87 are CMOS quad 2-input non-inverting data selector/multiplexers 74C157. U76-U78, U88, U89 and U105 are contained in a single 74C906 HEX CMOS buffer. U80-U83 and U96 are contained in a single 74C906 HEX CMOS buffer. U75 and U79 are quad clocked D latches 4042. U91-U93, U97-U98, U100, U103, U106-U108 are comparators. U90 , U94 and U104 are dual 4 channel multiplexer/demultiplexers 4052. U99 is a MC1406L 6 bit D/A converter manufactured by Motorola. UllO, U112, U119, U127 and U128 are inverting buffers. U115 and U116 are 74C85 CMOS 4 bit magnitude comparators. U117 and U118 are 74LS258 data selector multiplexers.0 U120 is a 6802 8 bit microprocessor manufactured, by Motorola. U121 is a 6821 interface adapter manufactured by Motorola. U124 is a INT-2716 EPROM. U122 and U123 are IK x 4 bit 2114 RAM memories. The following is a listing of resistors and resistor packs found to be satisfactory in the preferred embodiment. The values specified for the resistors are for 1/4 watt, 5% tolerance fixed carbon resistors unless otherwise specified: R36-RN12, RN17-RN20 and RN25a-RN25m are eight 10K ohm series resistances in a pack 316B103. RN23a-RN23m are 100K ohm parallel resistances in- each pack 314A104, PflGE βΘl ACMK .CF* &SET M 8 DEL ΣFILE.ΣF DEL MUXRQH.LX RLQAO ΣDOH ΣF'IFILE STRB ΦQΘβø STR0-$8@Θθ S7RP=*FSM LOiiO-PQHRUP LO D=SLFTST LOAD-INPUT LOAD=INTERR L0AO=RECEVE LOAO-PARSET LOAOs∑NTSVC CURP=$7BQ LOAO-PARTBL CURP-t7F8 LOAD-VECTOR BJX=NUXRON MO-ifLP EXIT εu " ϊύ 3 _ . OMPI WIPO PAGε øθl POURUP . SA 0 POURUP 80018 00081 NAN POURUP 88020 OΘO02 ******* VERSION 05 - 11 - S3, S U 0 *************** 08030 08003 * 00040 00004 THIS MOOULE IS εNTRY FOINT TO ACTUAL ACtVJX 08850 00085 PROGRAM. IT HANDLεS HARDUARE INI TIALIZATION AND 00060 88006 I-IINDS UP IN A UAIT STATε LOOKING FOR ITS MUX OO078 00007 sεLεcT LiNε TO Bε ACTiuATεo. 88888 88QQ8 βQ89Θ 08889 001 O 80010 PT LLE-8Q . REL •301 I Q øOOl IP 8000 PSCT 00120 08012 XD F POl-JRUP OΘ 130 00013 REF PI . STACK, INTεRR . PECε'JE FRRFLG OO140 88014 (.£F OεCODε, SYNCH4. D 1 GOUT . TRYCTR 00150 βOθlS XRεF LARGε, HI NARK, MIDDLE, PARTBL, XSAUE Θø lάø 00016 XR F LOMARK, UTOFGJ LEVEL . RAUIN, RECTNE øøl 70 00817 XR F ιιετεR . DURA, INPUT- SLFTST O lSø OOO I S XR F PARSFT, COUNT - BLNKTN 00190 00019 Θ02O0 08028 * 00210 88821P OOOΘ 8F POURUP sεi 00220 80022P 0081 7F Θ001 A CLR PI +1 ACCεSS DDRA 00230 00023P 0004 86 FF A LDAA #$FF SεT PAø - PA7 AS OO240 Q0824P OO06 B7 0000 A ST A A PIA OUTPUTS VIA DDRA 00250 08025P 0009 S6 3ε A LDAA ttssε ENABLE PRA AND SET CA1 00268 08O26P 800B 87 8001 A ST A A PIA+1 AS INPUT, CA2 AS OUTPUT 0Θ270 80027P βooε 7F 8Θ82 A CLR PIA+2 SET PB0 - PB7 AS INPUTS O2S0 80028P 001 1 36 17 A LDAA #$1 7 εH BLε PRB AND SET O029O 88029P 0013 87 8883 A ST A A CB1 AND CB2 HS INPUTS 00300 88030P 0016 36 OA A LDAA ir$ΘA 00310 0003 IP 001$ 87 0080 A S TAA PIA Mi T MUX RεADY cooε 00320 000 2P 0018 sε 0000 A LDS trSTACk SεT STACK POINTER 00330 00033P 00 IE BD 0000 A JSR SLFTST PERFORM SELF-DIAGNOSTICS 00340 00034P 0021 30 TSX 00350 00035P 0022 4F CLRA 003-30 Θ0036P 0023 09 :ERO OEX 80370 00837P 0024 A 7 00 A ST AH β, X ZERO ALL RAM 80350 00033P 0026 0800 A CPX #$0000 DONE ver' 00390 00839 p 0029 _.e> FS 0023 εnε zεpo WO OΘ4O0 0Q040P 002S 86 CD A LDAA #$CD I NIT "LARGε" L IMIT 00410 0004 IP 002D B7 0 0000000 A STAA LARGE 00420 00042P 0030 36 44CC A LDHA IN IT HI ARK LIMIT 00430 00043P 0032 B7 00000000 A STAA HIΠARK 00440 00844P 0035 $6 2A A LDAA #$2A IN IT LOMARK L IM T 00450 08045P 0037 37 OΘOO H STrlA LOMARK 00400 0OQ46F 0Q3A 26 5F A A LDAA #$5F INI T "MIDDLε" LIMI T Θ04 0 0004 P 0030 B7 0000 AA STAA MIDDLε 00488 80Θ4SF 003F 86 2D AA LDAA #$20 IN IT FREQUENCY PARAMETER OΘ430 O0O43P 8041 B7 8000 AA STAA tιετεp 00500 Θ0050P 0044 cε 004F A LDX tt$0Q4F INI T INTERR TONE CTR 00510 0tJ051P 0047 FF 0000 A 3TX DURA 00520 00052P 004A cε OPF A LDX #$8?FF INIT REcεvε UAIT I O DATA CT 00530 0Θ053P 0040 FF 0080 H STX Rεcmε 00531 08054P 0050 cε 2FFF A LDS #$2FFF 054O 00Θ55P 0053 FF 0000 TX BLNKTΠ 08550 00056P 0056 BO 0080 JSR INPUT GO CHECK FOR SPECIAL REQ 00560 8Θ057P 8059 BO 0808 INT R JSR INTεRR SELεC TED i INTERROGATE LINE 00570 Θ0O5SP 8Θ5C BD 8888 JSR RECEVE RECEIVE DATA gy _3-«ϊ _ - * OMPI PAGE 882 POURUP . SA - β POURUP 08588 0Θ059P 8Θ5F Bδ 8881 A LDAA XSAVE+1 0059O 0I3O60P ΘΘ62 81 7F A CMPA #$7F 006O0 88861P 8864 22 IF 8885 BHI ' AGAIN IF so, GO Dεcooε 00618 Θ0062P 8866 B6 8888 A LDAA XSAVE 88620 00863P 8069 81 88 A CMPA # 80 ΘΘ630 O0064P 8868 22 18 8085 BHI AGAIN øø64ø 08065P 886D 86 8B A LDAA *$8B oTHεp.uisε, RεpoRT A 00658 08866P 886F B7 8888 A STAA ERRFLG NO RεspoNsε ERROR < U > 08668 00O67P 8872 70 ■ 88ΘΘ A TST AUTOFG IF NOT, CHECK FOR AUTO- INTER 80678 0086SP 8875 27 1 8891 BEQ OUTPUT NOT AUTO- NTεRR, R AL ERROR 80688 88869P 8377 S6 3888 A LDAA LEVEL MAS AUTO-INTERR, CHK CURR. L 88698 88Θ78P 887A 27 15 8091 BEQ OUTPUT IF SO, REPORT. NO RESPONSε Ef? 80788 888 IP 0Θ7C 4A oεcA owεRuisε, TRY NEXT LεvεL UP 80718 88872P Θ07D 87 8888 A STAA LEVEL 80728 88873P 0888 7F 8888 A CLR ERRFLG O0738 ΘΘΘ74P 8883 20 D4 Θ059 BRA INTER GO TRY AGAIN ITH NEW LεiΕL 80740 88875P 0085 BD 8888 A AGAIN JSR PARSET Θ8758 88076P 8*388 BD 8888 A JSR Dεcooε Θ8768 00877P 888S BD 8888 A JSR SYNCH4 SYNCH ON DεCOOεD DATA 8077O 88Θ78P 888E BO 8030 A JSR COUNT 88788 88879P 8891 BD 8888 A OUTPUT JSR DIGOUT 88798 Θ8888P 8894 81 UAITl NOP 80880 88081 P 8895 20 FD 0094 BRA AITl 00818 88882 BND TOTAL ERRORS 88888— 88000 " "*S* 5? gtV: * _OMPI IPO PAGε 001 SLFTST . SA'ø SLFTST 88018 OOøøl NAN SLFTST 08020 00002 **.***.*.* VFRSION 84 - 88 - 83, S U 0 ****.***.**.**#*.** 00038 ΘΘO03 * 88048 0ΘΘO4 THIS MODULε is εNTεp.εo ON A SVSΓEW RεsεT 80Θ5O 88885 ANO PεRFO.RMS A SFLF TFST OF THF ON-BOARD COMPUTεR 88068 80806 SYSτεN. A RAM TEST IS DONE FIRST FOLLOUFD BY A 00070 88007 cπεcKsuti τε$τ OF wε PROGRAM PRon 88888 00088 RεL 8 128 80012 SO F SLFTST 08138 00313 XP. F BEGADR, ENOADD, PIA 88148 00014 t 88158 80015 * 80160 80016P OOOø cε 8800 A SLFTST LDX #$8080 START ADDRESS 08170 00017P 0003 4F STORε CLRA 08188 080 ISP O084 A7 08 A STAA Θ . X sεT εvεp.v oτπεR 8Yτε TO 8 30198 βθθ 19P 0006 88 lUX POINT TO Nε T BYTε 00200 88O20P 0007 SC 87FF A PX #$S7FF oonε YεT? 80218 88021P OøOA 27 07 8013 BEQ LOAD 88220 O0O22P OOOC S S66 F FFF A LDAA #$FF 88230 ΘQ023P oooε A A77 0 088 A STAA 0, X SεT RεMAINING BYTεS TO ALL 1 80240 ΘΘ024P 8818 88 INX POINT TO NεxT BYTε ΘO250 83825P 8011 20 F8 3883 BRA sτoRε Kεεp GOING 00260 08O26P 0013 cε SOOO A LOAD LDX ≠$soββ START ADDRεSS 80270 00027F 0016 A6 00 A L0AD1 LDAA ø, x cεr 8vτε 882S8 00028P 0018 26 OF 00, 29 BN εRROR BYTε SHOULD sε 0 08298 0Θ029P 801 A 08 INX POINT TO NεxT BYTε 00300 00030P 83 IB 8 8CC 87FF A CPX #$87FF DONε YεTT 08310 0003 IP 8Θ1E 2 _?7r 10 00 30 Bεύ ε ιτ 00320 88e332P 8020 H A6t> 00 A A LDAA 8, X cεT Nε T BYTB ΘΘ330 80033P 0822 8 SI1 FF AA CMPA #$FF BYTε SHOULD Bε ALL rs 88348 00034P 0024 26 03 0000.29 8Nε FRROR 88350 Q8*335P 0026 83 INX POINT TO Nε T BYTε 80360 00036P 3027 20 D 0816 BRA L0AD1 Kεεp GOING 80370 80037P 8029 86 14 A εRROR LDAA #$14 DECIMAL 28 = BAD RAH 00330 0003SP 0028 37 8888 A REPORT STAA PIA ERROR REPORTεD 00390 0ΘΘ39P 002E 28 FB 0Θ2B BPA P.εPORT LOCK UP MUX 08480 OOO40P 0030 EXIT RTS TOTAL FRRORS Q0OOO--ΘOOOO OMPI *n war* "•*** SUBS " - ' i ∑ * £__ Λ, IPO . PAGε 001 INPUT . SA* 8 INPUT 90Θ10 NAM INPUT 00028 00802 *.*.**.*.*.* VFRSION 85 - 18 - 83, S U 0.*#*#.*.*.*.**.*.***** 88038 80003 .* 00040 88884 .* THIS MODULε HANDLεS INITIAL COMMUNICATION 00050 88885 .* UITH THε NOVA CQNPUTεR. IT IS AN INPUT ONLY 00O68 80806 .* RQUTINε UHICH IS LOOKING FOR SPFCIAL FUNCTION 00070 88887 .* RFQUεSTS AS TABULATBO BεLOU IN ORDεR OF INCREAS¬ øøøSø OøβøS .* ING NOVA GεnεRATεo oεciNAL COMMUNICATION cooεs 08188 38818 .*.*:**;* COOε .*:**.*.*.*.*.*.* FUNCTION .*.*.*.*.*.*.*.*.*.**.*.*.*.**:*.*.* øøll ø øøøll * 112 8 - 7, UAIT UITH NO-RFSPONSε TIMε 88123 0Θ012 .* 114 88 - 255, CUSTOM FRFQUεNCY SεLεCT 38138 OΘ013 * 116 8 - i5, LεvεL sεLεc.τ cooε 08140 88014 * 119 8 - 7, INTεRROGATε DURATION, 7 = OH. 08158 88815 00150 88816 .* 80170 80817 OPT LLε=88, RεL øθlSø 8881SP 0880 PSCT 00190 88819 XDFF INPUT 08280 88828 XRFF PIA, NεTεR, T P, DURA, LNGFLG, XSAV 88218 88821 XRFF AUTOFG, LεvεL, RεcTi-tε, UA∑Ttiε, TQNTNE 88228 88822 XRFF BLNKTM 80230 88023 .* Θ8248 00024 -* 88250 00325P Θ80Θ 7C 8800 A INPUT INC AUTOFG SETUP AUTO INTεRROGATε O0260 00O26P 0083 86 8F A LDAA #$8F STARTING LεvεL 88278 0OΘ27P O085 B7 3888 A STAA LεvεL Θ8288 88Θ2SP 3838 BD øøCF P JSR cετcoε GO cεT cuRRεNT cooε 88298 88829P 888B 74 A CMPA #$74 cπεcK FOR LεvεL sεLεcT 83338 88e338P 388D 26 13 30. BNE CONT IF NOT cπεcK FOR CONT 33318 3Θ831P 888F BD 80AF "p JSR CHANGε UAIT FOR COMMAND TO CHANGε 33328 88Θ32P 8812 B- ? 0880 A STAA LεvεL S ' ε sεLεcτεo LEVEL 88338 33833P 8815 7F 0888 A CLR AUTOFG DE-ACT IVATε AUTO INTεRR 88348 88034F 0Θ18 BD 38CF P INPJ' Tl JSR cετcoε GεT COMMAND 3Θ35Θ 30035P 83 IB 81 74 A CMPA #$74 LOOK FOR sεLεCT COMMAND 88360 88336P 88 ID 25 F9 8818 BNE INPUT1 88378 38837P 80 IF BD 83AF P JSR CHANGε NOU LOOK FOR NFXT COMMAND 83388 O0338P 8822 81 77 A CONT CMPA #$77 CHεCK FOR CONTINUOUS COMMAND 88398 88039P 8Θ24 26 29 834F BNE CUSTOM IF NOT, CHεCK FOR CUSTOM 30483 83848P 0825 BD 8ΘAF P JSR CHANGE GFT DεSIRεD TONε DURATION 33418 8884 IP 0329 31 87 A CMPA #$87 CONTINUOUS RεoυεsT? 83428 33342P 0828 26 83 8838 BNE C0NT1 IF NOT ■ 33438 &3843P øf>20 7C 3883 INC LNGFLG SFTUF CONTINUOUS 88448 88844P Q338 Λ8 C0NT1 ' ASLA MUL TIPL Y BY 2 TO GεT OFFSεT 00458 38R45P 8331 CF 3883 H LDX #TONTMF ADDRεSS OF DURATION CONSTANT 33460 33846P 8834 FF 8888 A STX XSALΈ PUT IN UORKING RεGISTεR O047Θ 03847P 8337 SB 8031 A ADDA xsAvε+i FORM ADDRFSS OF DFSIRεD DURA 88488 88048P 3ι33A S. 8881 A STAA xs-Avε+i 38498 88849? 8Θ3D FF 8888 A LDX xsAvε cεT ADDRεss OF oεsiRεo DURAT 80588 88850P 8848 εε 88 A LDX 8, X cεT oεsiRεo DURATION FROM TA 08513 8035 IF 8842 FF 8883 A STX DURA SFTUP FOR INTεRR '33528 ~Q8(352P 8845 BD 88CF p C0NT2 JSR Gετcoε GεT NOVA TRANSMISSION 88538 83353F 0848 31 7ι" ' 7 ' A CMPA #$77 INSIST ON ANOTHεR 119 8054Θ 33854P 884A 26 F F99 8β0>. 45 BNε C0NT2 80558 0I3955P 834C BD 88AF P JSR CHANGε UAIT FOR ANOTH R NOVA TRANSM - 03568 88856P Θ04F 81 72 A CUSTOM CMPA #$72 CHεCK FOR CUSTOM FRFOUεNCY 88573 88857P Θ051 26 18 8883 BNε MεTR2 IF NOT, CHFCK MετεR2 R8Q. 08588 8Θ053P 0O53 BD 88AF P JSR CHANGE LOOK FOR VALUF OMPI PAGε 002 INPUT . SA 0 INPUT 059O 00Θ59P 0056 B7 0008 A STAA METεR GOT I T 0Θ680 83068P 0859 BD OOCF P INPUT2 JSR cετcoε GcT COMMAND 08618 3806 IP 805C 81 72 A CMPA #$72 HANT CUSTOM AGAIN 08628 80062P Θ05E 26 F9 0059 BN INPUT2 00638 80063P 0068 BD ΘOAF P JSR CHANGε GOT IT, UAIT FOR NEΛ 00648 88864P 0063 SI 78 A MFTR2 CMPA #$70 cπεcK FOR MετεR2 pεa. 08658 03065P 8065 26 25 008C BNE MεTR3 IF NOT. cπεcK tιετR3 03668 08066P 0867 BO OOAF P JSR CHANGε UAIT FOR oεsiTεo UAI T τnιε 03678 00067P 036A 48 HΪLA MULTIPLY USεR 'S εNTRY BY2 00630 00068P 0068 Cε 8038 A LDX #UAITMε ADDRESS OF UAIT TIME TABLE 80698 80069P OOe ' E FF 3000 A STX xsAvε ADDRESS TO UORKING PEGISTεR 03700 00070P 0071 88 0081 A ADDA xsAvε-i FORM ADDRFSS OF DESIRFD UAIT 80713 0007 IP 0074 B7 0001 A STAA xsAvε+i 08720 80872P 0077 FF 8808 A LDX xsπvε cεT ADDRεss OF oεsiRεo UAIT O073O 00073P 007A εε 00 A LDX o . x Gεr oεsiRεo UAIT τιnε 00748 8Q074P 807C FF 0003 A STX RεcT ε sεnip FOR Rεcεvε 08741 88075P 8Θ7F FF 0000 A STX BLNKTM 8O750 QQ076P 0082 BD OOCF P INPUT3 JSR GETCDE GεT NOVA TRANSMISSION 88768 00377P 0085 31 70 A CMPA -#$70 08770 00078P 3087 26 F9 3032 BNE INPUT3 MUST BRACKBT VALUε UITH 112 08788 00079P 0089 ED OOAF P JSR CHANGE UAIT FOR NFXT COMMAND 00798 8Q8S8P 088C 81 71 A MεTR3 CMPA #$71 CHECK FOR MFTER3 RεQ. 80808 00081P 008F 26 38 8098 BNE CHKLIN IF NOT, UAIT FOR LIN # OøSlO 00082P 8093 86 IE A LDAA #$1E sεnip FOR METER3 08820 00083P 8092 B7 0888 A STAA METER 00830 00084P 0095 BD OOAF P JSR CHANGE UAIT FOR LINE# 00840 00085P 0098 BD OOCF P CHkLIN JSR GETCDε GεT CURRεNT cooε 00858 00086P 889B 31 63 A CMPA #$63 CHECK FOR HALID LINE # 00360 8O087P 0090 22 F9 0098 BHI CHkLIN INSIST ON IT 08870 80038P 009F fo OA A LDAA #$0A GOT IT. REPORT TO NOVA 00880 08089P 08A1 37 8800 A STAA FIA 08890 8039QP 00A4 CF 7FFF A LDX #$7FFF SETUP DELAY FOR HARDNARE 08900 0089 IP O A7 09 Tiπε DEX SETTLING OF OFF-HOOK DETεCT 00910 80892P 00A8 25 FD Q0A7 BNE Turn COUNT IT DOUN! 00923 00097P 00 £6 0082 A LDAA PIA+2 CLεAR ANY FLAGS PIA+2 GεT COMMAND #$7F CLεAR HIGH BIT TFMP SAME AS LAST COMMAND CHANGε IF SO UAIT FOR CHANGE #$0F LOOP PIA+2 GET COMMAND AGAIN 01058 00106P 0ΘC1 34 7F A ANDA #$7F 31060 08107P 00C3 Bl 0000 A CMPA TEMP 01070 00138P 00C5 27 F7 ΘOAF BEO CHANGE 01080 0Θ109P OOCS B7 0000 A STAA TEMP CHANGED . SAVE NEU COMMAND 01090 001 8P 08CB S7 0000 A STAA FIA ECHO COMMAND TO NOVA 01108 301 UP OOCE 39 RTS OH I O 30112 * 01123 83113 * 31133 00114P OOCF B6 8002 A GETCDE LDAA PIA+1 GET COMMAND 01148 00115P 80D2 84 7F A ANDA #$7F CLEAR HIGH BIT 01158 88116P 8ΘD4 87 0000 A STAA TEMP SAVE COMMAND PAGε 003 INPUT . SA -8 INPUT 81160 øøl 17P 8807 B7 8838 A STAA PIA εCHO TO NOVA 01170 0Θ1 ISP øøDA 39 RTS øl lSø 00119 .* 0119Θ ΘΘ120 .* O1200 83121 εND TOTAL εRRQRS 88888— øøøøθ PAGE 881 INTεRR . SA 8 INTεRR 88818 88881 NAM INTεRR 88828 88882 ****.*** vεRSION 05 - 85 - 83, S U 0 .***********•** 83838 30003 * 88048 8ΘO04 THIS MODULε HANDLεS GENERATION OF THE 88058 08035 INTERRGATε SIGNAL USεD TO ACTIVATε THε MεTεR 88068 88806 εNCODER AT THε SUBSCRIBER 'S SITE. 80078 88007 THE TYPE OF METER IS NOU ASSERT INED FROM THE 88388 00008 LINε NUMSεR AND THE PROPER FREQUENCY OF TONE IS 88098 83889 THEN GENERATED. 88100 80010 88110 00011 30120 00012 OPT LLE=88. REL 80133 øOOl P 0800 PSCT 08148 00014 XDEF INTεRR 80158 80015 XREF METER . PI ■ TEMP ■ LNGFLG 80168 83816 HREF RAUIN, READNG, DURA, LEVEL 86170 00817 t 00 ISO 00018 t 00198 QOO 19P 0880 cε 0008 A INTεRR LDX #RAUIN 00280 00Q28P 0803 4F CLRA 0Θ210 0002 IP 0004 A7 08 A LOOP STAA Θ . X ZFRO S8RIAL DATA 00228 83022P 0006 OS INX BUFFER AREA 00233 00023P 0007 8C S7FF A CPX #$87FF 83348 O0824P 308A 26 F8 3884 BNE LOOP HHE'- i DONε. 80241 80025P 8ΘΘC OF SEI PREVENT FURTHER INTERRUPTS 80242 Q0026P 8880 86 08Θ8 A LDAA LεvεL GET CURRENT LEVEL 88243 Q0027P 0010 48 4 SLA 30244 ΘO023- P 0811 48 ASLA MOVE TO UPPER 4 BITS 00245 00029P 3812. 43 ASLA 00246 0001 ' OP 8013 48 ASLA 00247 00831 P 0014 SA 00 ORAA #$0D ADD A BCD 17 -'j° NOVA 08248 0OO32P J J 557 0000 A STAA PIA CONTROL LEVEL & V/.JT STATUS 00258 00033P 0 19 36 LDAA #$76 SNI TCH MUX TO 08268 00034P 0015 3001 H * T AA PIA*-: TRANSMIT MODE 33270 00035P oo ιε 0000 A LDAB MF τ z GETUFPΞQ TCQHΪ T NT 082S0 Q0036P 0021 0000 H X IT STAB MP * ?H"T ~REQ CODE 03290 00037? 0024 FF 0000 A XMIT2 LDX DURA DURATION COW- I T EP 00300 00033? 0? 7 F5 0000 A XMIT1 LDAB TEMP 00313 QΘ839P όόirt 36 A LOU LDAA #$35 38323 00043P 032C 87 0303 A STAA PIA*-3 INTEROG TE OU 38330 0004 IP 002F 5H DECS zETUP LOU 1 2 PERIOD 83348 00042P 0870 26 F3 002A BNE LOU PONE ? 00350 00043P 0032 0090 H LDAB τεM° GET FP?n CONS TINT AGAIN 00360 0035 '-> Jt A HIGH LDAA #$?-ε 08370 0834?? 3077 57 000 A STAA PI *3 INTERROGATE HIGH 00330 00046.' 007A 5A oεcB SETUP HIGH 1 2 PERIOD 03390 0004 F 003B 9β« F3 0035 SHE HIGH TOTALLY DONE* 08488 3004SP 003D 09 oεx ONE PERIOD DONE 08413 00049P 003E 26 F7 0027 BNE XMIT I ALL DONE YET ? 00420 00050F 0040 7D 0080 TST LNGFLG CHEC, FOR LONG ^EQUEz T 00438 0005 IP 0043 35 DF 0024 BNE XMIT2 30440 30052? 0045 36 15 LDHH #$16 SET MUX TO INPUT MODE 08453 38853P 0047 B7 0003 A STAA PIA+7 ONCE AGAIN 38468 88054P 004A B6 0001 A LDAA PIAτ2 CLEAR REMAINING FLAGS 00478 88055P 0Q4D RTS YES - EXI T 38488 08056 εND TOTAL εRRQRS 00000—88800 OMPI WIPO ' P Gε θθ Rεcεvε .sή--ø Rεcεvε 8081Θ ββøøl NAM Rεcεvε 00Θ20 88882 ; *.*.*.*.*.** vεRSION 85 - 18 - 83, 8 U 0.*.*.*.*#.**.*.*.*.**.*.** 88Θ38 83Θ03 88840 000O4 THIS MODULE HANDLεS INPUTTING OF RA SFRIAL Θ8858 00O05 DATA STRεAM. FAST GLITCHFS ARε RεjεCTεD AND 88868 00886 COUNTS PROPORTIONAL TO THε UIDTH OF FACH HIGH 88878 OΘ087 AND LOU STATε Rεcεivεo ARε sτo?εD IN MεMORY. 83888 08838 εvεn ADDRεss STARTING AT πεx sβββ CONTAIN wε 88898 88889 HIGH STATε COUNTS HiLε THε LOU STATε COUNTS ARε 88108 8Θ813 STORεo IN THε ODD LOCATIONS. 88118 88811 TM 88248 88024P B7 8888 A STAA GLITCH CONSTANT 8Θ258 88825? 0000 4F CLRA CLεAR ACT∑vε RεGisrεR 88268 88826? il fir 5F CLRB CLεAR AUXILIARY RεG. 88273 88327? 880F BD QΘΘΘ P NQCHG JSR DεLAY ASTε sonε τιt-ιε 88233 8Q32SP 8812 7D 8082 A TST PIA+2 RεAD PORT OΘ290 88829P 3315 2A rb* ΘΘΘF BPL NOCHG GQHε HIGH vεT? 30338 08Q38P 8817 4C 7NCA Yεs, FOR l CYCLε 38310 0883 IP 8818 BD 8888 P CHG1 JSR DEL Y UASTE SOME TINE 33323 88832P 88 IB 70 0802 A TST PIA+2 READ PORT 30333 88033P 031E 2B 83 8823 8MI CHG2 STILL HIGH? 88348 88834P 8823 4F CLRA NO, MAS GLITCH 88358 83335? 3321 28 FC 888F BRA NOCHG KEEP TRYING FOR HIGH 3Θ36Θ 38835? 8323 4C CHG2 INCA HIGH FOR ANOTHER CYCLE 83378 88337? 0924 B Bll 8888 A CMPA GLITCH LARGER THAN A GLITCH? 38338 88038P 3327 2 266 FF 8818 BNE CHG1 NOT YET 88398 88839P 3029 BD 8888 P HIGH1 JSR DεLAY UASTE SOME TIME 30438 ΘΘΘ48P ΘΘ2C 7D 8882 A TST FIA+2 READ PORT 08410 08Θ4 IP 032F 2A 83 8834 BPL CHGLOU STILL HIGH? 88428 38Θ42P 3831 4C HIGH2 INCA YES, STILL HIGH. 88438 88843P 81332 23 F5 8329 BRA HIGH1 KEEP READING 30443 88Θ44P 3334 5C CHGLOU INCS A LOU DETECTED 38453 83Θ45P 3335 BD 8380 P CHGLU1 JSR DELAY UASTE SOME TIME 88468 83846? 3838 7D 3882 A TST PIA-ι-2 READ PORT 38473 88347 P 8Θ3S 2A 85 8842 BPL CHGLU2 STILL LOU? 38438 88848? 833D. IB ABA NO, HAS GLITCH 33498 88349? 333ε 16 TAB FOR TIMING ONLY 88503 38Θ5ΘP 3Θ3F 5F CL.RB FILL IN MISSING COUNTS 38518 3Θ851P 8848 23 FF 3*331 BRA HIGH2 KEEP READING 1 'S 88528 33852P ■ 8842 5C CHGLH2 INCS STILL IS LOU. 33533 8Θ353P Q843 F-l 0000 A CMFB GLITI3H BIGGER THAN A GLITCH? 33548 88854? 8346 26 EC 8035 BNε CHGLH1 NOT YET 38553 38855P 8848 A7 83 A STAA 0, X YES, ON TO 8 'S STATE - 88563 QQΘ OP 884A 38 INX PT. TQ NEXT BYTE 83578 88Θ57P 884B 4F CLRA A RεG. NOU AUXILIARY Rε 8Q588 88858P 8Θ4C SC 0088 A CPX #LEVεLl ALL DONε vεr? OM?I_ ~ PAGε 802 Rεcεvε SA β Rεcεvε 00590 08059P 0Θ4F 2E Q07F BEQ EXIT IF SO 0O6O0 00868P 8051 5C INCB CATCH UP i 80610 00Θ61P 8852 01 NOP FOR TIMING 30620 ΘQ062P 0053 01 NOP ΘΘ630 Θ3063P 0054 BD 0088 P L0U1 JSR DELAY UASTE SOME TIME 38640 00064P 0857 7D 8803 A TST PIA+2 READ PORT 38658 ΘΘ865F 085A 2B 03 005F BMI CHGHI STILL LOU ? 80663 00066? 835C 5C L0U2 INCB Yεs 33670 ΘΘ867P 005D 20 F5 0054 BRA L0U1 εεP RεADING 00638 Q0068P 005F 4C CHGHI IhCA A HIGH DετεcτεD > 88693 00069P 8868 BD 0888 P CHGHIl JSR DELA i- UASTE 50Mε τnιε 00708 33Q7QP 8063 7D 0802 A TST PIA+2 Rε D PORT 08718 0007 IF 0065 IB 05 006D B'll CHGHI2 STILL HIGH ? 00720 00072? 0068 IB ABA NO, HAS GLITCH 38738 0007?? 0069 16 TAB FILL IN MISSING COUNTS 30748 00074P 006A 4r CLPA CLR AUXILIARY RFG 00753 QQQ75P 0Θ6B 20 EF 005C BRA L0U1 kεε? RεπoiNG o -s 80768 08076P 0060 4C CHGHI2 INCA STILL IS HIGH 03778 00077P 006E Bl 8080 A C;I»A GLITCH SIGGεR THAN A GLITCH ? 00730 08073? 0871 26 ED ooeo BNE CHGHIl NOT -,'ετ 08790 00079? 0873 E7 00 A STAB 0. X YES, MOVE TO NEXT STATE 0880Θ 80888P 0075 03 INX PT TO NEXT BYTE 08818 08081? 0076 5F CLRB B REG NOU AUX REG. 08828 80882P 8377 SC 0000 A CPX #LεvεLi ALL DONε YFT ? 88S30 00083? 087A 83 807F BEQ ε n CF SO 08843 88884? 0Θ7C 4C INCA CATCH UP i 00358 0Q025P 007D 20 AA 0(329 BRA HIGH1 NOU GO LOOK FOR 1 ' S 00863 000S6P 037 F 33 EXI T R TS 00370 00037 80380 00088 * * SUBROUTINE TO DεLAY FOR FRεQ kεYING 00S90 00089 r 08908 03090P 0080 8803 A DE H I' STX X3AVE SH ε x RεcisTεp ctOSAl 000 IP 0033 0000 A 3T,)A TEMP 90918 00092P 0026 B6 0001 A LDAH SAVE*-! 00911 00097P 0083 31 3F A CMPA #$7F 00918 OOQ J P Q03B 23 03 -3095 ELS DELA ,'1 00930 08095? 003D FE 0000 H LDX B Mk TM 00943 00096? 0038 OOOO A STX RECTME 00958 00097? 0093 28 06 389B BPA OεLA) 2 08360 00093" øøi>5 FE øOOO A DELAY1 LD-. VSri'Ε FOR TIMING ONL Y THESE 08970 00099P 00?? FF 0008 A 2T S Vε TUO INSTRUCTIONS = 1 1 MICRO- 009 0 001 OOP 0093 B5 0000 A 0εLAY2 LD A TE'IP ETR:E"E -ΞGIΪTER 00390 0 10 IP 089E 31 FE H CMPA ≠$FE CHECK FOR -ZEC OVEFFLOU 01000 00102? QQAQ 4A no c SHI CE IF Q U EF^LOU 01013 00103? 08A2 cl FE MPS tr$FE CHECk -OR B-PEG O' l ER^LO 01020 0 10-*P 00H4 OOF 2 SHl ' BOVER IF OVEP c LOU 01030 031 5P 00A6 36 0008 A LDHA RECCTP 31040 08106P 00A3 26 07 08B2 BNE DELH '7 01350 Q3107P OOAB B6 0001 A LDAH PECCTR+1 01351 00103P QOAE 81 7F A CMPA #$7F 0105208109P OOBO 23 33 OODA BLS NOBLNk 01060 0011 OP 00B2 FE OOOø A DEL YS LDX XSA"E 1870 331 UP 00B5 33 ItiX IF SO . IDENTIFY UI TH TUO 01871 08U2P 0886 3008 I-I PX #LE.'EL_ 01072 8811 ? 00B9 27 C4 Oø.-r BEQ E IT 1098 88114P OOBB B6 8800 A LDAA RεCCTR 81180 83115P ΘOBE A 7 øø A STAA 0 ■ X SAVE THIS COUNT UHICH 31113 08116P 03C3 83 INX RεppεsεNTS THE LENGTH OF PAGE ΘΘ3 Rεcεvε . SA ^ Θ Rεcεvε øll l l 3Θ117? 8ΘC1 8C βθθø A CPX #LεvεLi 01112 801 ISP 88C4 27 B9 887F BBQ εxιτ 81128 Θøl 19P ΘΘC6 B6 8881 A LDAA RεccτR+ι THε BLANK SPACε Θ1133 8812ΘP 88C9 A7 38 A STAA 8, X 81131 88121 P 88CB 88 INX 81132 03122P ΘΘCC 8C 8000 A CPX #LEVEL1 81133 88123P 88CF 27 Aε 887F Bεa εxιτ 81148 88124P 8ΘD1 88 INX 81141 88125? 8802 8C 0800 A CPX #Lε>4. : ELl 31142 88125P 38D5 27 A8 387F B Q εx T 81153 0Θ127P 3ΘD7 FF 8833 A STX sAvε 81168 88123P 83DA 7F wvfcϊø H NOBLNK CLR RεCCTR CLεAR TOO LONG COUNTεR 81173 38129P 88DD 7F øøø 1 A CLR RεccτR*-ι IT 'S 2 BYTES HIDE 31 138- 80138P øβεs 85 83 A LDAA #$83 GET DεLAY CONSTANT 81198 88131P 00E2 4A LOOP oεcA COUNT. IT DQUN 31288 8Q132P 00E3 26 FD 38E2 BNB LOOP DQNε γετ-τ . 81213 38133P øøES B6 8088 A LDAA TEMP RεsTORε A RεGisτερ 81228 88134P ββεs ΓJΓ 8888 A LDX XSAVE RεsTOP.ε x RεcιsτεR 81233 88135P βoεs 33 arς GO p.εcεivε sotiε MORε 31248 38136? 8&εc 4A AOVFR όεcA PRεvεNT QVERFLQU 81250 88137? øøEO S7 8380 A STAA TEMP SAVE IT Θ1268 88133? 80FΘ 28 øl 38F3 BRA CHKDNE CHECK IF TOO LONG SINCE CHG 31278 00133? 83F2 5A sovεR DEC3 PREVεNT QVεRFLQU 81288 0O148P 83F3 FE 8088 A CHKDNε LDX RECCTR GFT TOO LONG CQUNTεR 81293 8814 IP 88F5 38 INX ANOTHεR CYCLε UITH QVεRFLQU IU388 88142P 38F7 FF Θ0Θ8 A STX RεCCTR UPDATF TOO LONG CQUNTεR 81318 Θ0143P 88FA SC 8888 A CPX RεcTiiε TOO LONG UITHQUT CHANGε? 31323 38144? 38FD 27 04 0183 sεo ALTXIT IF SO, FXIT AND REPORT ERR 81333 88145? SOFF 86 37 A LDAA #$87 USE DIFFEP.εNT DεLAY CONSTANT 31348 80146P 8181 23 DF 88E2 BRA LOOP GO BACK TO pεcεivε 81358 88147P 8133 31 ALTXIT INS UNDO JSR TO DεLAY 81353 Θ0143P 8184 31 INS 01373 03149? 8135 7ε 887F P JMP εxιτ 31333 00158 E/-/0 TOTAL εRRQRS 00000-00000 SUBSTITUTE SHEET OMPI PAGE 001 PARSET . SA 'β FARSET 80010 30081 NAM PARSFT 00020 00002 ***#.**.* vεRSION 05 - 85 - 83, S W 0 *************** Θ0Θ30 00883 * 00040 00004 THIS MQDULε ANALYZES THE RA METER READING 08050 00005 COUNTS TO oετεRMinε wε TRANSMITTED BAUD RATE. 00860 00006 THIS IS ACCOMPLISHED BY FIRST IDENTIFYING 00870 00007 THE KNQUN STRING OF BCD 14 '8 UHICH ACCOMPANY THE 00080 00008 READING AND DETεRMINING THε RεLATVε COUNT 00093 08009 UIDTHS UHICH SHOULD ALSO εNASLε DεCQDING OF THF 00108 00013 UNKNOUN RεADING I TSFLF. ftO H O 0081 1 80120 00012 00130 00013 OPT LLE=30 ■ REL 33140 00014P 0000 PSCT 08153 00015 XDEF PARS C T 00160 00016 λREF LOMAPK, HI ARK. I DOLE- LARGε, RAN IN 00173 00317 XPEF LεvεLi . rεMP. xsAvε- FRRFLG 0 ISO 00013 XREF LOUCTR, HICTR . XSAVF1 , ADRPTR 00190 00019 * 08200 00020 00210 00021 P 0000 OF PARSFT SEI 00220 00322? 8881 CF 3030 A LDX fRAHIN GET RAU DATA COUNTS POINTER 00230 0Θ023P 0004 86 08 A LDHB 0 ■ X GET A LOU LεvεL RAU COUNT 00240 00024P 0006 OS PLUS: INX 00250 00325P 0007 S_ 0000 A CPX iLEVELl 00260 00026P OOOA 2_.6_: 03 008F BNE PLUS3 00270 80027P 880C 7E 00C6 P JMP ERROR 00230 00023? OOOF 38 PLUS. INX 00290 00029P 0010 SC 0000 A CPX XLEVELl 00700 00030P 0013 26 03 0018 BNE OVER 00313 0083 IP 0015 7E 00C6 P JMr ERROR IF NO sεouεNcε oετεcτεo 00320 Θ0032P 0813 A6 08 A OVER LDAA 0. X cεT A FAN Lou LεvεL COUNT 88338 30033P 001 0000 H STAA TEMF 00340 00074P 0010 10 SBA C0MPAR8 LAST TUO COUNTS 00350 00075P 001E 2B 02 0022 BMI A8SVL1 00360 00036 P 0020 20 01 0023 BRA C0MPR1 08370 00077P 0022 40 ABSVL1 NEGA GεT ABSOLUTE "ALUE OF DIFFFR 00730 00033P 0023 81 OA CQHPR1 CMPA #$0A 80390 00039P 0025 2F 08 882F BLE INCLOU 00400 00048P 8027 7F 0000 A CLR LOUCTR 03418 0004 IP 002A F6 OOOø A LDAB TεMP HAVEN ' T FOUND SEQUENCE YET 00420 00042P 002D 20 D7 0006 BRA PLUS2 kEEF TRYING 00430 00047P 002F 7C 0300 A INCLOU INC LOUCTR LAST TUO MATCHED 00440 00044P 0032 F6 0080 A LDAB TεMP 00450 00045P 0035 86 QE A LDAA #$oε 00460 00046? 0077 Bl 0000 A CMPA LOUCTR ENOUGH SEQUεNTI L MATCHES YE 00470 00047P Q03A 3F 02 003E BLE SETLQU IF SO 00480 0004SP 0Q3C 20 C3 0006 BPA PLUS 2 IF OT- kεε? TRYING 00490 00049P 007E 54 sε∑Lou LSRB HAVE I T" . DIVIDE BY 0O5OO 00050P 003F F7 øøøø A STAB LQMAPi. TO FORM LOMARK PARAMETER 00510 Θ0051P 0342 09 MINUS 1 DEX BACK UP 1 RAU COUNT TO HI LV 00520 00052P 0047 8C OOOø H CPX #PAUIN 00530 00053P 0046 7ε 0QC6 BEQ ERROR 0Θ54Θ 00054P 8048 86 00 A LDAB Θ . X GET RHU HIGH LE»εL COUNT 00550 00055P 004A 86 0000 A LDAA Tε ? GET LOU DATA COUNT 00560 00856P 0040 S3 OF A ADDA #$0F 00570 88857P Q04F 11 CSA 14 - 14 TRANSITION COUNT SHO 00588 00853? 0050 2A FO 0Q4i BPL MINUS 1 BB LARGεR THAN LOU DATA COUN -SUBSTITUTE SHEEt OMPI PAGE 082 PARSET . SA ' Θ PARSET 88598 00059? 3852 FF 8880 A STX xsAvε 88688 00068P 8855 89 MINUS6 DEX 00610 8886 IP 8856 89 DEX 0O628 88862P 8857 89 DEX MOVε POINTεR BACK 6 COUNTS 88638 88863P 8858 39 DEX 88648 00064P 8859 89 DEX 88658 00O65P 885A 89 DEX 8(3668 08866P 805B FF 8838 A STX ADRPTR 88678 Θ0067P ββsε cε 8888 A LDX #RAUIN 33633 88868P 8361 FF 8888 A STX XSAVE1 88681 8*38S9P 8864 FF øθøO A LDX ADRPTR 88693 88070? 8867 B5 øøøø A LDAA ADRPTR 38738 03871P 886A Bl øøøø A CMPA XSAVE1 88718 38372P 8360 22 8A 8879 BHI . AHEAD 38728 8O073P 386F B5 3881 A LDAA ADRPTR*- 1 88738 88874? ΘΘ72 Bl 8881 A CMPA XSAVεi+l 88743 38875P 8875 22 82 8879 BHI AHεAD 38741 00875? 8877 28 4D ββCS BRA ε.RRQR 8O750 O0377P 8879 A6 8ø A AHFAD LDAA ø,x cεT 1-ιεxτ HIGH LEVEL COUNT 08768 8387SP 887S B7 8831 A STAA TEMP*-1 80773 88879P 8Θ7E 18 SSA CHεcK FOR sεδuεNcε 88788 8Q8S8P 8Θ7F 2B 82 8883 BMI ABSVL2 88798 88831? 8881 28 81 8884 BRA CQMPR2 88888 888S2P 8883 48 ABSVL2 NEGA 88818 88Q83P 8884 81 8A A C0MPR2 CMPA #$8A 88328 83884? 8886 2F 88 8898 BLE INCHI 88838 83885? 8888 7F 8883 A CLR HICTR 88848 38386? 8Θ8B FE 8883 A LDX XSAV 83858 08887P Θ33E 23 32 8342 BRA MINUS1 IF NO sεQuεNcε vεT 30868 88083? 8Θ9Θ 7C 8888 A INCHI INC HICTR 88878 8Q089P 8893 F6 3881 A LDAB τειiρ-ι-1 33388 3009OP 3895 86 83 A LDAA #$Θ3 88398 88891P 8898 Bl 8003 A CMPA HICTR εNQUGH MATCHεs at A sεQuεNcε 33988 33892? 8893 2F 32 889F BLE SETHI 08913 8e3893P ΘΘ9D 20 B6 8055 BRA MINUS6 88928 80394P O09F 17 SBTHI TBA 08930 8Θ095P 38A3 54 LSRB 88948 Θ0096P ββAl F7 0ΘΘ8 A STAB TEMP SAVε 1/Ξ THE 14 - 14 COUNT 03958 88097? 8ΘA4 54 LSRB 88968 38398? 88A5 F7 8831 A STAB TENP+1 SAVE 4 THE 14 - 14 COUNT 33978 38893P 08A8 F3 Q8O0 A ADDB TEMP 88988 38108P 88AB F7 øøøø A STAB MIDDLE MIDDLE PARAMETER GεNERATE l l 88998 88181P 38AE F5 3001 A LDAB TEMP÷I GεT 1---4 COUNT BACK 31888 83182P 0QB1 54 LSRB 31818 08133? 88B2 F7 øøøø A STAB τεt-ιp SAvε 8 THε 14 - 14 COUNT 81328 38184? 88B5 FB 8881 A ADDS τει-ip+1 31338 88135P 8388 F7 øøøø A STAB HI MARK 01340 38186P 88BB BB 0888 A ADDA TEMP 81850 83187? øøSE 24 f ) 2 0ΘC2 SCO SETLRG 31863 88188? 88C3 86 FD A LDAA #$FD SεT LARGE TO DEC. 253 31873 38133P 08132 B7 8838 A SFTLRG STAA LARGF LARGE PARAMETεR GENERATED 81883 8811 OP 8ΘC5 39 EXIT RTS 81890 001 UP 38C6 86 3D A ERROR LDHA #$eo ■ COULDN ' T SYNCH UP Oi l OO 00112P 88C3 £? øøøø A STAA ERRFLG OH IO 08113? 38CB 20 F8 08C5 BRA EXIT 81128 88114 BND TOTAL ERRORS ΘQ888— 8Θ0Θ0 SUBSTITUTE SHEET PAGε ooi oεcooε SA θ oεcooε 88818 88081 NAM oεcooε 88828 30082 ******* VεRSION 05 - 34 - S3- 11 0 *************** 88838 80883 * 33848 88004 THIS NQΩULε CONVεRTS THε RAU SεRIAL DATA 88853 00385 CONTAINED IN "RAUIN" TO A SEQUεNTIAL BLOCK OF 80868 38006 1 ' S AND O ' S THIS IS THF FREQUFNCY l- EYING VERSION $0878 00837 AND IS P REPARED TQ RεTRεiVε THε METER REHDING øθθSO 08808 εvεN IF BOTH THε NARROUεST MARk BITS ARε MISSING 80893 80809 EYTεs ARε 1 ST cπεckεD FOR A mo LAPGE CONDI TION 00108 88010 UITH A SUBSEQUENT BREAKING UP INTO 2 SEPπRATε 08113 8801 1 "0" BITS NBXT T ε RεMAINING BIT MARK DATA 03120 88012 IS STRIPPED OUT LEAVING ONLY DATA BITS IF THREε 08130 0001 3 DATA BITS ARε FOUND IN A RO , THF MICDL8 OWE 80148 03014 Jo THROUN OUT 80158 83815 88163 80016 0Θ1 78 03017 OPT LLE=SO, RεL 08188 8801 SP OOOø FSCT 80198 00813 XDEF oεcooε 08230 00020 XPEF ADRPTR . BYTPTR . RAUIN, LEVEL 1 , TEMP 08218 80021 XRFF LARGE, HIMARK, LOMARK. MIDDLE- XSAVE 38228 Θ0022 * 08238 88023 * 03248 30024P OOøθ OF Dεcaoε sεi DISABLF QFF-HOOk INT 00250 30825? 0001 7F 8000 A CLR TEMP CLR TFMP STORAGE LOCATION 88263 83826? 0004 cε 0888 A LDX trLEVELl INI T oεcoBεo DATA 38270 00827P 00*37 e F 0000 A s : BYTPTR STORAGε AREA POINTER 88280 00023P OOQA cε 0000 A LDX #PHUIN INIT RAU INPUT O TA 08238 00023? 0000 FF øøøø A D8C0D1 STX HDRPTR STORAGE AREA POINTER 03300 00030? 0 10 BD 08B9 P JSR ELANk 00310 08031? 8013 A6 80 A LDHA Θ . X GET RAU DATA BYTE 38320 Θ0072P 0015 Bl 8888 A CMFA LARGB CHECk FOP TOO LARGE 00330 00037P 001 3 FF 00S9 BhI 4.RGBYT IF 30. BREAK INTQ 2 O 'S 00J 0 00034P 001 F6 OOø 1 A LDAB ADRPTR*- 1 GET LOUER BYTE OF DATA HDDR 00353 00035P 3010 C4 01 A NDB ttøl TEST FOP ODD OR EVEN 0Θ368 30Q35P OOIF J"* 87 0ø 28 BEQ LOUTST EVEN = LOU I 'QL TAGE c l BIT • 30370 00037P '0031 SI øøøø A CMFH HIMARk UHS ODD USE HIGH VOL T ONS 30730 00023P 0024 23 OC 00 32 BHI DATA DATA OR MHPk BIT ? 00338 08039P 0826 20 05 OO, 2D BRA MARk IS A MARK BIT 08433 80848P 0023 SI øøøø A LQUTST CMPH LQNHRK MAS εvεu, USE LOW COL * CONS 0*3410 0004 IP 003B . ? 05 8032 £HI DATA IF THIS IS A DA TA BI T 08428 00042P 0020 F 3008 MARk CLP TEMP OTHEFUISE. A MARk BIT 00470 00047? 0070 20 64 OO, 96 BPH i -l EXE IT IGNORε AND GεT HE"T B τ£ 00440 00044P 0032 7C ørtøO A DATA INC TEMP FLAG HNOTHER DATA BYTE 00458 00045P 0035 C6 OJ A LDHB #$03 CHECk FOR 00460 80046P 0037 Fl øøOO A CMP3 TEMP THREE IN A P0U 08478 QQ047P 003A 26 3C 00 78 BNE 3TRBIT IF NOT 00430 ΘQ04SP 003C 03 INX PT TO NE' T RAU DA TH SI IE 03498 QQQ4 P øøJO E6 00 A A LDAB ø . X GεT NEXT BYTE 03588 00858P 007F FF OOOø H H srv XSAVE SAVE THIS HDDPESS 00510 8005 IP 0042 09 oε- y RESTORE ADDRESS POINTER 80520 00052P 0043 B6 0001 A LDHH .-.SA'iε+l GET LOUER BYTE OF HDDPESS 08530 80053P 0346 84 01 A At 'OH #$31 TεST FOR ODD OR EVEN 38543 00854P 0043 87 0051 εεo. LOTST IF εvεπ. usε LOU VOL T CONST 00550 00055? Q04H F ' I 0080 A CHFS HIMARK QTHεRUISε, USE HIGH OLT CO 08560 00056P 0040 23 OF oo; JE BLS DATA1 CHECk FOR DATA OR MARk 00570 00057? 004F 20 85 0056 BRA FOUR 4 IN A ROU, MAKE DECODε THIN 00530 0QO5SP 0051 Fl 0838 A LOTST CMPS LOMARK USε LOU VOL T CONSTANT PAGE 8Θ2 oεcooε . srt --ø oεcooε 88590 88859P 8854 23 83 885E BLS DATA1 CHECK FOR DATA OR MARK 80600 00068P Θ058 7A 8888 A FOUR DEO TEMP 3 IN A ROU. NEXT ROUND. . 0061Θ 8886 IP Θ059 Fε øøøø A LDX BYTPTR RETRiεvε oεsτ. ADDRεss. 88528 0I3062P O05C 28 34 3392 BRA INCBYT Nε T BYTε MILL Fopxε ADJUST 38630 O0063P ββsε 39 0ATA1 DEX POINT TQ MIDDLε BYTε OF THRε 88648 0O064P 885F FF 8888 A STX XSAVE SAvε x RεcιsτεR 88658 88865P 8862 ES 80 A LDAB 8, X GεT MIDDLε BYTB 88653 88855P 3854 38 INX . εsTORε cuRRεNT poiNTε? 88673 88067P 8365 86 3881 A LDAA XSAVε+1 cεT LouεR BYTε OF X 80538 08868P 8868 84 81 A ANDA #$81 CHECK FOR ODD OR EVEN ADORES 38698 8*3e369P θ'36A • ?? 8C 3878 BEQ STRBIT IF MIDDLE BYTε εvεN, SKIP AD 88738 88878P Θ85C Fl øøøø A CMPB MIDDLε MIDDLε BYTB DATA OR NARK 33713 88371? 0Θ6F 22 87 0873' BHI STRBIT IF DATA SYTF 38728 88872P 8871 FE 8388 A LDX BYTPTR omεRuisε, FORCE 3RD 80730 88873P 8874 89 DEX SIT TO 2ND POSITION 138748 88874P ' 8875 FF 8888 A STX BYTPTR. Θ875Θ 88875P 8873 5F STRBIT CLRB PRELOAD A "ø" err O0760 80876P 8879 86 8081 A LDAA ADRPTR*- * ΓESΓ FOR ODD O0770 88377P 887C 84 81 A ANDA #$01 OR EVEN ADDRESS 00783 O087SP 0&7F 26 82 80S2 BNE LOUBIT ODD ADDRESS, SIT = "ø" 3Θ790 30379P 8388 CS 81 A LDAB #$θl EVEN ADDRESS, BIT = "1 " θøSøø 30088P 8882 pε 8888 A LOUBIT LDX BYTPTR GεT DESTINATION ADDRESS 33818 00881? 8835 ε7 88 A STAB 0, X STORE THIS DATA BIT 88828 88082P 8837 89 8892 BRA INCBYT GO COMPLETE NEXT BEST. ADDR. 88838 88883P 8889 4F LRGBYT CLRA PRELOAD "8" BIT 88848 88884? 888A FF 8888 A LDX BYTPTR GET DESTINATION ADDRESS 80858 88885P 388D A7 øø H STAA 8, X STORE A "0" BIT 00868 OθøSSP 883F 83 INX GET NEXT DESTINATION ADDRESS 88373 0Θ037P 8033 A7 88 A STAA 3, X STORE A 2ND "O" BIT 88883 388S8P 8892 88 INCBYT INX POINT TO NEXT AVAILABLE 38898 38889? 8393 FF 8888 A TX BYTPTR DESTINATION ADDRESS O0500 88898P 8096 cε 8880 A NEXBIT LDX ttLεvεu Θ3918 88891P 8899 FF 0888 A STX xsAvε 88928 88892P 839C FE 8883 A LDX ADRPTR 88938 88893? 889F 88 INX 83948 88Q94P 38A0 FF 8888 A STX ADRPTR 38950 88895P 00A3 B6 8888 A LDAA ADRPTR øø5όø 88896P 88A6 Bl 8888 A CMPA XSAVE 0097O 88897P 88A9 22 3D 8QB8 BHI εxιτ 38988 08893P 88AB 25 88 38B5 BNE NεXBTl 88998 38899P 88AD B6 8881 A LDAA ADRPTR* 1 31888 88188? 88B0 Bl 8881 A CMPA xsA ε*-ι 81818 βø tdlP 38B3 22 83 8383 BHI εxπ 31820 38132P 88B5 FE 8880 P NEXBTl JMP DECODl 0103Θ 88183? 88B8 39 EXIT RTS 31848 33134 .* 81353 øøiø5 * THIS ROUTINE CHECKS FOR THE INTER-MεTεR BLANK 81868 Θ8186 * PATTBRN. IF FOUND, THE LEVELl PATTERN IS 81873 38107 * INTERRUPTεD BY TUO "FF 'S" BRACKFTING A 811333 88108 * COUNT OF ø TO 256 REPRESENTING THE UITDTH OF 31898 33189 THE BLANK SPACE εNCOUNTεP.εD. 311QΘ 83113 t 31113 8811 IP 88B9 He 88 A BLANK L LDDAAAA .. Q 8,, XX GBT RAU DATA BYTB 31123 88112P 88BB 26 29 83E6 BNE RETURN 01I21 88113? 88BD A6 31 A LDAA I, X 31122 88114? 33BF 27 25 8QE6 BEQ RETURN 81138 8Θ115P 83C1 A6 83 A LDAA 3, X H1148 88116P 83C3 26 21 8ΘE6 BNE RεTURN SUBSTITUTE SHEET OMPI PAGE 803 DECQDε . SA = β DεCOOε 81141 00117P 8ΘC5 A6 84 A LDAA 4, X 81142 001 ISP 0ΘC7 27 I D ββεs BEQ RETURN 81158 00119P 8ΘC9 εs 81 A LDAB 1.. X GET SLANKTIME COUNT 81168 00123P 38CB FE 3888 A LDX BYTPTR STORE TO ADDRESS 01178 ø 1 IP 88CE 88 FF A LDAA #$FF 31180 Θ8122P øθDΘ A7 88 A STAA Θ, X 8U9Θ 8 123P 30D2 Θ8 INX O1200 88124P Θ0D3 F7 33 A STAB Θ, X 81218 Θ0125P 0ΘD5 OS INX 31228 ΘΘ126P 8ΘD6 A7 88 A STAA 3, X 81238 00127? 0008 88 INX 81248 8Θ128P 88D9 FF 8888 A STX BYTPTR 81258 88129? 38DC FE øøøø A LDX ADRPTR 81268 88138? 88DF 68 INX MOVE RAU DATA POINTER 81270 38131? 88E8 OS INX PAST THE INTER-METER 81280 O0132P øOEl Θ8 INX IDENTIFYING PATTERN 81298 80133P 0ΘE2 38 INX 81383 Θ0134P 88E3 FF øøøø A STX ADRPTR 31318 Θ 135P 88E6 39 RETURN RTS 81328 0Θ136 END TOTAL εRRQRS øθθøθ—øøøøø OMPI WIPO PAGε Θ01 SYNCH4 . SA - Θ SYNCH4 88818 88881 NAM SYNCH4 88828 88882 .**.*.*.*.** VERSION 85 11 - 83, 8 U 0.****.*.******.**.** 88030 88883 * Θ0040 88834 * . THIS MODULE CONVERTS THE DECODεD PATTεRN OF 00050 880O5 * 1 'S AND β 'S OUTPUTTFD FROM THF DεCODε MODULε 88060 38886 * INTO THε RεCOGNIZABLε BCD DIGITS TRANSMITTED 08878 83887 .* FROM THE Rεtιoτε M. i. u. oεvicε. SYNCH-UP θe3ΘS8 38888 .* REQUIRES 3 CQNsεcuπvε BCD 14 1 'S UHILε LOSS OF 88898 øøøøi? .* SYNCH OCCURS uπεN MORε THAN 4 N0N-1.4 'S ARE 08180 38818 * DETECTED. 38118 88811 * 00128 33812 .* 08138 88313 OPT LLE=88, RεL 88140 88814P øøøø PSCT O0150 88815 XDEF SYNCH4 88168 33015 χorp RεADNG, εNDADD, BBGADR, BYTPTR, ADRPTR 381 8 83817 XRFF LεvεLl , SYNCFG, NONFG, CTR14, BYTSAV, ERRF 88188 88818 XREF LOUCTR, TEMP, MεTRCT, XSAVε, XSAVεi øø 181 Θ0319 XRFF DIGITS 88198 Θ0Θ20 * 38288 Θ0021 .* 88218 08822P 8838 ?F 8883 SYNCH4 CLR SYNCFG INIT ALL MODULE PARAMETERS 0022Θ 88823? 8883 7F øøøø CLR NONFG NQN 14 COUNTER 88233 30O24P 8886 7F øøøø CLR CTR14 # OF CONSECUTIVE 14 'S CTR 88231 0ΘΘ25P 8Θ09 cε øøøø LDX #Lεvεn 88232 8ΘΘ26P 33ΘC FF øøøø STX xsAvεi 38248 88027? 388F CE FFFF LDX #DIGITS -1 8Θ258 ΘΘΘ23P 8012 FF øøøø STX εNDADD FOR DIGQUT 08268 08829? 8815 FF øøøø TX BYTPTR DIGIT STORE-TO ADDRεSS 80270 8083OP 8313 cε FFFF LDX #RBAONG ■ 1 BOTTOM OF 1 'S AND β 'S STORA 00280 0O33 IP 8813 FF 3388 STX ADRPTR 1 ' S AND 8 ' 8 POINTER 88298 38832? 331E BD 8883 GETDIG JSR FBYTE MAKE DIGIT OUT OF 4 1 'S AND 38388 Θ0833P 8321 7D 8338 TST SYNCFG ARE UE IN SYNCH? 88318 3ΘΘ34P 8824 2D 8353 BEQ SYNCH IF NOT, GO GET IN SYNCH. 00323 88835? 3826 B6 8883 A LDAA BYTSAV IN SYNCH, GET THIS DIGIT 38338 83835P 0025 81 0E A CMPA #$βε IS IT A 14? 83348 8Q837P 0O-.fi 26 85 8832 BNE N0N14 IF NOT, GO HANDLE IT 38350 00Θ38P 8820 7F øøøø A CLR NONFG is A- 14, ?εsετ NONI 4 CTR. 88350 Θ0839P 3833 28 53 3385 BRA STORIT AND GO STO,Rε THE 14 O8370 88848P 3832 7C øøøø A NQN14 INC NONFG NQN 14, COUNT HOU MANY øø.JSø 8384 IP 8835 F6 0088 A LDAB NONFG MAX # ALLOUED 83393 Θ0342P 8038 Cl 85 A CMPB #6 REACHED THE MAXIMUM? 38488 3ι 343P 0O3A 49 3885 BLS STORIT IF NOT STORE VALID DATA 30418 88844P 883C 3883 A CL. NONFG TOO MANY, PREPARE TO RE-SYNC- 03428 38845P 883F ,-t- 8388 A CLR SYNCFG FORCES A RE-SYNCH 88438 30846P 8342 CS IC A LDAB #28 BACKUP ADRPTR TO BEGINNING 83448 38Q47P 8844 BO 387A P JSR DECPTR OF CURRENT NON-14 GROUP 38453 88048P 3347 FE 880O LDX BYTPTR 88463 83849P 3Θ4A 83 INX 8847Θ 80358P 834B 33 INX 0043O 0005 IP 884C 88 INX 88490 OΘ052P 8840 88 INX 33580 Θ3053P 884E FF 0388 A STX BYTPTR 80510 O0354P 0051 28 CS 88 IE BRA GETDIG .GO SYNCH UP l O0520 88855 .* 33533 83358 * THIS SECTION GETS THE MODULE BACK IN SYNCH BY 88540 88357 * DECRεMεNTING THE ADRPTR 1 ,*0S1 TIQN AT A TIMε OΘ550 80058 * AND LOOKING FOR 3 14 'S IN ft ROU SUSS . J i rf i ώi iw.- -U_.-_. * OMPI PAG 802 SYNCH4 SA 0 SYNCH4 88568 80059 * 08570 OOO60P Θ053 B6 OøOO A A SYNCH LDAA BYTSAV GET CURRENT DIGIT 0O5SΘ 0806 IP 8856 81 0βEε A A CMPA #$βε IS IT A BCD 14 ? 00590 Θ0O62P 0053 27 O OrtA 0088 S644 BEQ MAYBε IF SO UF MAY HAVε SYNCH ΘO6O0 08863? 005A 7F 8883 A A CLR CTR 14 IF NOT kEEP LOOKING 08613 80Θ64P 3850 C6 33 A A LDAB #3 00620 00065P O05F BD 087A P JSR oεcPTR ADDRESS POINTER BACK 3 30638 80866P 8862 20 8 A 38 IE BRA GεTOIG GET NEXT DIGIT 00648 08867P 0064 F6 0000 A A MAYBE LDAB CTR 14 HHD 3 14 ' 8 IN A ROU YET? 88653 88Θ68P 0067 Cl 0 022 A A CMPB #2 08668 80069P 0069 22 0 055 00007 700 BHI INSYNC IF SO UE 'Rε BACK IN SYNCH' 00678 0(3Θ7QP 006B 7C 0 0888888 A A INC CTR 14 IF NOT CHALK UP THIS ONF 006S8 3807 IP 306E 2300 A AEE 8800 ι IεE BRA GεTϋlG AND KEEP TRYING ' 00690 08072? 0078 7 ? CC 0 0880088 A A INSYNC INC SYNCFG IN SYNCH. FLAG IT 83780 0ΘΘ73P 3073 C6 OC AA LDAB #12 30713 Q0Q74P 0075 BD 007A PP JSR DECPTR BACKUP ADD.RESS PTR 3 DIGI TS 00720 00075P 0073 20 A4 83 IE ERA GETDIG GO BACK OVBR BUT UITH 3Ϊ NCH 80770 30076 * 00748 Θ0077 * THIS SECTION SIMPLY BACKS UP THB 1 'S AND β 'S 03753 00878 * POINTεR AORPTR) BY TtfE HUMBBR CONTAINεO IN 88760 00879 * THε "8 " REGISTER UPON ENTRY 00778 00088 * 08783 0008 IP 0Θ7A FE øøøø A DFCPTR LDX ADRPTR GET ADRPTR 00790 I3Θ8S2P 8870 88 LOOP INX BACkUP 1 88888 08383P 007E 5 oεcB COUNT IT DOUN 00310 80084P 807F 25 FC øø, 70 Btiε LOOP DONE YET? 00328 00085P 0881 FF 0000 A STX ADRPTR IF SO GO SACK 00833 Q0036P 0084 39 RTS DO IT 80S4Θ 08087 * 80850 00083 * 00360 OO089P 0885 FE øøøø A STORIT LDX BYTPTR GFT CURRENT STORE POINTER 30870 80098? 0083 86 8000 LDAA BYTSAV GεT CURRεNT DIGIT βOSSQ 88091 P 3088 AT 08 STAA O . X SAV8 IN DIGIT STQRAGε AR8A 00390 00092P 0080 09 oεx 00900 0005JP OQ-?ε FF 0000 A STX BYTPTR POINT rg NEXT AVAILABLE LOC 00918 00094P 0091 23 SB OOIF EPA GETDIG CONTINUE 88920 00895 *S ' 00938 80096 * THIS SECTION USES ADRPTR TO POINT TO BEGINNING OF 8<3948 00097 K 4 CONSECUTIVE SITS UHICH SHOULD BE CONVERTεD TO 8*3953 80898 * A SINGL8 BCD DIGIT 30960 30099 * OUTPUT DIGIT GOεS TO BYTSAV, ADPFTR 13 -4 ON EXI T 00970 001*38 f 30330 QQ1Q1P 0893 7F Oθθθ A FBYTε CLR BYTSAV CLEAR DIGIT STORAGE LOCATION 08993 0 182P 0096 0000 A LDX ADRPTR GET ADRPTR 81000 08103P 0899 C6 04 A LDAB #$04 TO COUNT # OF BI TS 01018 0 104P 0098 A6 00 A GBTBIT LDAA 0. X GET H BIT 01023 00105P 0390 SI FF A CMPA #$FF 01021 00106? 089F 3F OOEΘ BBQ BLll Ck 01333 00107? OOAl BA 0080 A A OPAA BYTSAV STORE IN BYTSAV TEMP 01848 0010SP 00A4 87 oooβ A S r A BYTSAV 01850 00109P 00A7 09 GBTBTl DB 01360 00110P 00A3 FF øøøø A STX ADRPTR 01100 001 UP 08AB B6 0000 A LDAA ADRPTR OH I O 38112? OOAE Bl OOOø A CMPA XSAVE1 01123 08U3P 00B1 3 ? OC OOBF BHI AHEAD 01 138 88114? 08S3 B6 0001 A LDAA ADPPTR÷l 01148 00115P 00B6 Bl ΘQQ1 A CMPA XSAVE1 +1 01150 38116P 88B9 22 84 ΘOBF BHI AHEAD IF NOT, KEEP GOING J^ -β. -J . I OMPI /,, WIPO PAGE 803 SYNCH4 . SA --0 SYNCH4 01160 88117P OΘBB 31 INS USE ALTERNATE EXIT 01178 øøl ISP ΘΘBC 31 INS -.' Θ11S0 øøl 19P Θ0BO 20 09 00C8 BRA EXIT 81198 0012OP ΘΘBF 5A AHEAD oεcs FINISHED ANOTHER BIT 81288 00121? øøCø 27 05 Θ8C7 BBQ DONE DONE ALL 4 YET? 81213 Θ0122P ΘΘC2 78 8008 A ASL BYTSAV SHIFT LAST BIT TQ LEFT 1 01220 88123? 0ΘC5 20 04 889B BRA GETS IT GET NEXT BIT 01230 Θ8124P Θ8C7 39 DONE RTS 01240 83125 * 01250 88126? 8ΘC8 CF 8838 A EXIT LDX #R£ADNG GET START OF DIGIT AREA 01260 88127? 8ΘCB A6 88 A ZERTST LDAA 8, X GET THIS DIGIT 01273 8812SP øøC026 3D 8ΘDC BNB sεrsεG IF NON-ZERO, DONE 01238 8Θ129P 88CF 88 INX GET NEXT DIGIT 131290 00130P 3808 8C FFFF A CPX #DIGITS- ■ 1 31338 88131P 3803 27 82 8807 BBQ 8RR0R 31318 33132? Q8D5 20 F4 øøCB 3RA Z8RTST Kεεp GOING 81323 88133P 88D7 86 OC A 8RR0R LDAA #$8C 8RR0R RεPORT 813.38 88134? 8ΘD9 B7 øøøø A STAA ERRFLG 81348 83135P 88DC FF øøøø A SETBBG STX BEGADR FOR DIGOUT 31353 38135? 88DF 39 RTS ALL OONF! 81360 00137 . * 01378 08138 * 31388 00139? βøE8 7F øøøø A BLNKCK CLR NONFG 81390 00140P 08E3 7F Θ888 A CLR LOUCTR 01480 Θ0141P- 8886 7F 8838 A CLR CTR14 81410 00142P 88F9 7F 8888 A CLR SYNCFG 01420 00143P ββεC 7F øøøø A CLR TEMP 01438 88144? 88EF 89 BLANK DFX 01448 08145? 88F0 A6 øø A LDAA 8, X 81450 88146? 38F2 BB øøøø A ADDA LOUCTR 01468 88147P 38F5 B7 øøøø A STAA LOUCTR 81478 00148P 88F8 ' 89 oεx 81488 O0149P 03F9 89 oεcNεx oεx 81498 03150P 88FA A6 OO A LDAA 8, X 815Θ0 03151P 88FC 81 FF A CMPA #$FF 31531 Θ8152P øøFE 28 85 3185 BNB NONNEG 3151Θ R8153P 3180 7F 3388 A CLR T8NF 31528 88154? 8183 28 EA 3QEF BRA BLANK 31538 33155? 8135 70 8888 A NONNεG TST TBMP 31548 881S6P 8138 26 83 813D BNB INCFLG 81558 83157? 818A FF 8888 A STX XSAVE 31560 8Θ153P 3180 B6 øøøø A INCFLG LDAA TEMP 31573 8Θ159P 3118 4C INCA '31580 ΘΘ16ΘP 8111 B7 øøøø A STAA TEMP 31593 33161? 3114 81 14 A CMPA #$14 31688 88162? 3115 22 82 811 A BHI CMPUTE 31613 08163P 8118 23 DF 88F9 BRA DECNEX 31620 8Θ164P 811A Fε 8888 A CMPUTF LDX BYTPTR 31633 88165? 31 ID 86 1A A LDAA #$1A 81648 88156? 31 IF A7 88 A STAA β, X 81658 88167P 3121 39 DEX 31668 80163? 8122 F6 8838 A LDAB LOUCTR 81678 83169? 8125 E7 38 A STAB 0, X 81688 ' 8Θ178P 3127 09 DEX 316 0 8Θ171P 8128 A7 38 A STAA Θ, X 81738 88172P 312A 89 DEX 81713 38173P 8128 FF øøøø A STX BYTPTR 31728 0Θ174P Θ12E 7F øøøø A CLR LOUCTR SUBSTi ' T ST?"""** OMPI ~ PAGE 884 SYNCH4 . SA ' Θ SYNCH4 81738 88175P 8131 7F 8838 A CLR TεMP 81748 38176P 8134 C6 81 A LDAB #$øl 81758 88177P 3136 FE 3883 A LDX SΛ 81768 38178P 8139 89 oεx 01770 88179? 313A 89 oεx 81788 Θ8133P 813B 39 oεx 31798 Θ0181P 813C 89 oεx 31888 Θ8182P 813D 7E 88A7 P JMP GεTBT. TOTAL 8RRQRS 0ΘQΘQ—388Θ0 SUBSTITUTE SHEE OMPI PAGε 881 COUNT . SA - Θ COUNT 00810 88881 NAM COUNT 08820 80002 ******* vεRSIQN 05 - 11 - 83, 8 U Q ******.*.******** 08038 88803 * THE DECODεD & SYNCHεD OUTPUT TO wε NOVA OR øøllø 88811 XDEF COUNT øø ' 123 83Θ12 XRFF BBGADR, εNDADD, ADRPTR, BYTPTR, TEMP 80130 83813 XREF XSAVE, XSAVE 1 , CTR14, CTR15, TRALL 33148 38814 XRFF DIGITS, METRCT 88158 88315 * 38158 88816 * 88170 88817? 8888 Cε 8888 A COUNT LDX iOIGITS 08180 88318P 8833 FF øøθθ A STX BYTPTR øøl9ø 88819? 8888 FF øøøø A LDX BEGADR 88208 88828P 8889 5F CLRB 33218 88021? 888A 7F 0083 A CLR CTR 14 83228 0O022P 8880 7F 8888 A CLR CTR15 00230 O0023P 8310 7F øøøø A CLR TεMP 88248 00824P 8313 7F 0000 A CLR CTRALL 8Θ25Θ Θ8025P 3816 7F øøøø A CLR METRCT Θ0260 00Θ26P 8319 A6 8ø A GTSTRT LDAA ø, X 83273 Θ8Θ27P 3Θ1B 81 1A A CMPA #$1A CK FOR INITIAL BLANK 83283 88828P 831D 27 3E 3Θ2D BEQ STRTDL 88298 Θ3829P 881F 5C . INCB 38388 88Θ38P 0020 Cl 83 A CMPB #$ø3 88313 88831 P 3822 27 17 Θ83B BEQ SETBBG 88328 88832P 002488 I.NX 33330 08Θ33P 8325 3C 8888 A CPX #DIGITS 88348 Θ0834P 8828 26 EF 3819 BNE GTSTRT 83358 88335P 882A ?E 813B P JMP GXIT 88368 88835? O02D A6 82 A STRTDL LDAA 2. X O0370 88837? 802F 81 1A A CMPA #$1A 8033O 88838? O031 26 E6 8813 BNE GTSTRT 88398 88839P ΘΘ33 36 FF A LDAA #$FF 88488 80843P 0035 87 øøøø A STAA MFTRCT 88418 83841 P Θ83S BD 010B P JSR CMPARE 83428 80042P 883B BD 88FD P SETBBG JSR CNTSTR 38438 38343 * 38443 83344P 863E 88 FETCH INX 33458 33345? 803F SC øøøø A CPX #DIGITS 88468 88846? 8342 27 25 Θ069 εεo FETCH4 88488 88847? 8344 AS 38 A FET1 LDAA ø, X 38498 813348? 8845 7C 8888 A INC TEMP 38588 88343? Θ049 31 8E A CMPA #$øε 14? 88518 83858? 8048 26 83 3853 BNB FETCH 1 33528 38351P 3840 7C øøøø A INC CTR 14 33538 88852P øø5ø 81 ΘF A FETCH 1 -CMPA #$ΘF 33548 88853? 0052 25 11 8865 BNE FETCH3 15 i 33558 88854? 3354 7D 8888 A TST CTR15 38588 88855P 3857 2605 3362 BNE FETCH2 38578 '33356? 8859 FF 8888 A STX XSAVE 08588 ΘΘ057P 8Θ5C F60000 A LDAB TEMP SAVE LQC. OF 15 88538 00058? 885F F7 3330 ' A STAB CTRALL PAGE 882 COUNT . SA 8 COUNT 00600 0OΘ59P 8862 7C 8000 A FETCH . INC CTRl 5 80610 0Θ068P 0065 81 1 A H FETCH3 CMPA #$1A 36? Θ0620 0006 P Θ067 26 05 8Θ3E BNE FETCH 8063Θ 00082P 8869 FF 8888 A FETCHAi STX ADRPTR 88648 Θ8863P 806C B6 3888 A LDAA TEMP 88650 00O64P Θ06F 81 ΘF A CMPA #$8F 08660 3Q065P 8871 23 58 88C3 BLS ERROR ENOUGH DIGITS? 38673 8086SP 0Θ73 S6 øøøø A LDAA CTR 14 ΘO630 00067P 8076 31 83 A CMPA #$03 8N0UGH 14 ' S ? 8Θ698 83Θ68P 0078 23 43 03C3 BLS ERROR 08700 08869P 007 A B6 0008 A LDAA CTRl 5 88718 0O070P 007D 81 02 A CMPA #$02 TOO MANY 15 ' S? 80720 00Θ71 P Θ07F 22 42 80C3 BHI ERROR OO730 Q0872P 0381 FE 8338 A LDX XSAVE G T LOC . OF 15 88748 88373? 3884 A6 81 A LDAA 1 , X METER ID 83758 88874P 0086 BD 0085 P JSR LASTOR 0Θ75Θ Θ8875P 0889 86 16 A LDAA #$16 "22 " DEL IMI TER 08778 00076P OβSS BD 08E5 P JSR LASTOR 38788 88877P 008E BS 0000 A LDAA CTRALL 30790 0007SP ΘQ91 81 8C A CMPA #$8C 88888 00879? 0893 22 08 3Q9D BHI BACkUP 08818 38888P 8095 36 05 A LDAA #$05 88828 83081 P 0097 88 FORURD INX 88833 08032P 0898 4A oεcA GO FORUARD TO I 30848 Θ8Θ83P 0399 26 FC 8097 BNB FORURD 88353 ΘQ0S4P 3098 28 86 88A3 BRA STRDAT 30860 00085P 0090 86 ΘB A BAC.<UP LDAA #$OB 08878 80886? 889F 89 BACK1 DEX GO BACKHARDS Ti 88838 80087? 00AO 4A oεcA 00898 00088P OOAl 26 FC 809F SNB BACK1 00900 0ΘO89? 0 A3 A6 03 A STRDAT LDAA Q . X 88918 38090? 80A5 BD 00E5 P JSR LASTOR 00920 00091P 00A3 A6 81 A LDHA 1 , X 80970 88892P OOAA BO 08E5 P JSR LASTOR 00940 00097P OOAD A6 02 A LDAA 3 '* 00958 08894P ΘOAF BD 00E5 P JSR LASTOR 08960 00895P 8832 A6 83 A LDAA 3, X 00973 00096? 00B4 BD 08E5 P JSR LASTOR 08938 00097? 00B7 A6 Θ4 H LDAA 4 • X 88993 30Θ98P 8089 ED 00E5 P JSR LASTOR 01008 80099P OOBC A6 05 A LDAA 5- X 01310 0010ΘP 003E BD 0085 P JSR LASTOR 31020 00101P 00C1 20 05 Q8CS BRA REINIT 01030 08182P 08C3 86 OC A ERROR LDAA #$βc 01040 88183P 00C5 BO 80E5 P JSR LASTOR 81358 0Q104P Θ0C3 7F 8000 A REIN I T CLR CTR 14 01860 0Θ105P Θ8CB 7F 8888 A CLR CTR 15 01070 00106P 08CE 7F 8888 A CLR CTPALL 01388 00107? 80D1 7F OOOø A CLR TEMP 01081 00103? 3804 FE 0000 A LDX ADRPTR 01032 00109P Θ0D7 SC 0800 H CPX #DIGITS • 31033 001 10P OODA 27 5F 013F BEQ E I 31093 33111? OODC BD 81 OB P JSR CMPHRE 01108 001 12P OODF BD OOFD P JSR CNTSTP 31128 831 13P 08E2 7E 883E P JMP F TCH 01130 08114 * 81148 88115P 0ΘE5 FF 0003 A LASTOR STX xsAvεi 81158 0Q116P OFS FE 8388 A LDX BYTPTR PAGE 883 COUNT . SA' Θ COUNT Θ11SΘ øøl 17P 8ΘEB FF 8ΘΘ8 A STX 8NDADD 01170 881 ISP ββεε 8C 87FF A CPX #$87FF 01188 80119P 88F1 27 89 Θ8FC BEQ LST0R1 01190 O 120P 88F3 A7 øø A STAA ■ 8, X 81288 0O121P Q0F5 08 INX 81210 00122P 88FS FF øøøø A STX BYTPTR 01220 8Θ123P 88F9 FF øøøø A LDX xsAvεi 01230 00124? 8ΘFC 39 LSTQR1 RTS Θ1240 08125 * 81258 8Θ126P 8QF0 86 1A A CNTSTR LDAA #$1A 131268 00127? 88FF 3D 84 0085 BSR LASTOR 81278 80128P 8181 BS øøøø A LDAA M8TRCT 31280 Θ8129P 8134 80 DF 33E5 BSR LASTOR 01290 88138P 8136 88 1A A LDAA #$IA 013Θ0 88131 P 8188 3D DB 8ΘE5 BSR LASTOR 01313 80132? 318A 39 RTS 01328 O0133 * N8TRCT #DIGI TS εxιτι 8, X #15 INCS METRCT #52 INC3 METRCT #128 INC4 METRCT #178 CMPAR1 METRCT #DIGITS EXIT1 #01 GITS B8GADR 31628 38161 END TOTAL ERRORS øøøOø—øøøøø PAGE ΘOl DIGOUT SA 0 OIGOUT 88818 88081 NAM DIGOUT 88828 38802 ******* VERSION 5 - 28 - 81, S U 0 **************** 0O038 30003 * 0O040 00004 THIS MODULE IS THE LAST MODULE IN THE MET8R Θ005Θ 00005 R8ADING CYCL8 IT CONMUNICATεS TH8 RεSULTS OF ΘΘO60 00006 THE ATTEMPT TO READ BACK TO THE CENTRAL OFFICE 00Θ7O 00007 D-G NOVA 3 COMPUTER THE COMMUNICATED DATA MILL 88888 08083 BE EITHER THE METER READING ITSELF IF A SUCCESS¬ 00090 O0005 FUL READ MAS ACCOMPLISHED < THE READING ILL BE 33108 øøø-O SUCCE8DED BY A BCD U 15" TO SIGNAL THE NOVA THAT 88113 0001 1 THE PEAOING IS NOU AVAILABLB ) ■ OR AN RROR CODε 38120 88812 INDICATING TH8 R8AD ATT8MPT HAS UNSUCCESSFUL 33130 88013 ERROR CODE IS H BCD 12 UHICH FLAGS 88148 08014 RECEVE AND SYNCH ERRORS ALL ERROR 88158 80315 CONDITIONS APE RELIEVED BY RES8TTING TH8 MUX 88168 88016 33178 ΘΘ817 88183 80018 OPT LL8=30, R8L 08198 OΘO 19P 3008 PSCT 88288 00020 XDEF DIGOUT 8821Θ 00021 XRFF ERRFLG, ENOADD- BEGADR, PIA 88228 00022 * 08238 Oøø23 * 08248 00024P øfløø OF DIGOUT SEI NQ INTERRUPTIONS PLEAS8> 08270 Q0025P 8881 B6 0808 A LDAA ERRFLG CHECK FOR READ ERRORS 88388 Θ0026P Θ0O4 27 05 888B BEQ READOT IF NONE. SUCCESSFUL READ 88290 00027? 0006 87 0800 A ERROR STHA PIA BAD READ. REPORT AND LOCk-UP 00300 00023? 0009 23 FB 0086 BRA ERROR LOCk UP MUX 83313 00829P OOOB FE 8308 A READQT LDX BEGADR GET START OF DATA TO MOVE 0Θ320 00830? OΘOE OF LDAA #$0F GET "DIGIT READY" CODE 00321 0003 IP 8810 BA 0003 ORAA PIA 80373 00332P 0813 B7 8008 STAA PIA TRANSMIT I T 88348 38033P 0016 B6 8003 STROBE LDAA PIA+3 READ STATUS REGIST8R 08350 00034? 0019 S4 48 ANDA #$48 LOOK FOR Cδ2 INT FLAG 00360 00035? 00 IB 27 F9 0016 BEQ STROBE IF NOT SFT kEEF LOOkING 00361 88836? 00 ID B6 0002 A LDAA PIAr2 CLEAR STROBE FLAG 00370 08837? 0020 AS 80 A LDAA Q . x STPOBC HCKNOULED8 Rεcεi"εo 00330 88833P 0022 S7 øøøø A STAA PIA TRANSMIT DIGIT 03390 88833? 0025 03 INX FOINT TO N8XT DIGIT O04OΘ Q004QP 0026 BC 8000 A CPX εNDADD M0V8D IT ALL YET ? 00413 80041? 0029 27 02 302D BEQ EXIT IF 20. ALL DONE 83428 00042? 0023 20 E9 00 L6 ERA STROBE NO . UAIT FOR NEXT ACk 08458 00043? 8020 S6 3082 A EXIT LDAA FIπ n -2 CL HR HNY EXTRANEOUS FLHG3 00451 03044P 0030 36 10 A LD H <r$10 NU BUSY CODE 03452 80045P 0Θ32 B7 0000 H STAA PIA X IT IT 08453 00046P 0035 39 RTS LEA"E> 0Θ47O 00047 END TOTAL ERRORS 00000—08808 C P" 'J 8 8 Ϊ im. -- _-__.il OMPI PAGE 801 DUMPIT . SA * Θ DUMPIT 00010 øøøθl NAM DUMPΣT 88828 ******* VERSION 04 - 88 - 83, 8 U 0 *************** 88838 øøøø3 * 88048 0Θ804 * THIS NODULE IS FOR DIAGNOSTIC USE ONLY. 88058 00005 * ENTRY IS MADE FROM ANYUHERE IN THE NORMAL PROGRAM 88368 0Θ886 * FLOU AND IS INITIATFD BY THE NQN-HASKABLB INTERR. 0øø7ø 83887 * LINE AS ENABLED BY A NOVA GEN8RAT8D A0DR8SS 96. 88888 ΘΘ0Θ8 * 88398 00O89 * 88133 øøølø OFT LLE=S0, REL 8ΘI1Θ 8831 IP 8833 PSCT 00120 80012 XDFF DUMPIT 08130 03813 XRFF PIA, DIGOUT, NDADD, POURUP, BBGADR 88148 88314 XRFF ERRFLG 38150 88815 * 08168 88816 * ' 88178 88817P Θ88Θ 8F DUMPIT SFI 08188 888 ISP Oøø 1 85 IF LDAA #$1F NOVA REQUEST 00198 88813? 0003 B7 8883 STAA PIA+3 ACKNOULEDGε CODE 88288 8ΘΘ28P 8836 CE 8838 LDX #$3888 BEG. ADDRESS OF DATA TO DUMP 88218 88021P 0039 FF 8383 STX BEGADR SAVE FOR DIGOUT 38228 00Θ22P 000C Cε 87FF LDX ■ #$S7FF END ADDRESS OF BLOCK TO DUMP 88238 0Θ823P 0OΘF FF øøøø STX FNDADD SAVED FOR DIGOUT NODULE 88248 83024P 0012 7F 8888 CLR ERRFLG CLEAR ANY ERRORS 00250 00O25P 0O15 3D 8888 JSR DIGOUT GO DUMP IT! Θ0251 Θ0026P 0018 81 NOP 88252 88827P 0819 81 NOP 3 ( 1258 80028P øøl A 33 RTI ALL FINISHED! 83278 Θ0829 8ND TOTAL ERRORS 88888 — øøøøø DMPI IPO P GE 001 ACMUX SA 0 ACMUX øøølø 00001 NAM ACMUX 08020 0ΘΘΘ2 ******* VERSION 05 - 11 - 83, S W 0 *************** 88838 88883 * 83840 88804 08858 88885 OPT LLE=8Θ, R8L 88058 Θ0O36B ΘΘQΘ BSCT ΘΘ070 00087 XDEF PIA, STACK, INTCTR . LEVEL . AUTOFG. RECCTR 30388 88008 XDEF METεP, SOURCE, ΩεST. OkCTR, LNGFLG, RECTME 88890 88009 XDEF ADRPTR . ENOAOD - XSAVE • TRYC TR, DURA 80183 000.0 XDEF GL I TCH . TEMP . LARGE ■ L OMARk HIMARK . MI DDL 38118 0081 1 XDEF BYTPTR . ZERCTR, ONECTR ■ BEGADR . ERRFLG 08128 88012 XDEF SYNCFG, NONFG, CTR14. BYTSAV . LOUCTR . HICT 30138 38813 XDEF XSAVE1 , ETRCT- BLNKTN, CTRALL . CTR 15 80148 0Θ814 * Θ0153 00015 * 30160 88016 4888 A PIA EQU $4008 PARALLEL ∑sQ ADDRESS 00178 88817 887F A STACK EQU $807F STACK POINTER INIT 88188 80018 * 00193 00015.? øøøø 8881 A ERRFLG RMS 1 ERROR CODES STORED HERε 88288 080208 3331 8001 A GL ITCH RMS 1 GLITCH COUNT ALL0U8D 00210 00021B 0002 0032 A SOURCE RMB SOURCε ADDR8SS ST0RAG8 30220 0O022B 8084 0002 A DEST RMB DEST. ADDR8SS STORAGE 08233 00Q23B 0006 0002 A TEMP RMB TEMPORARY STORAGE OΘ240 3QQ24B 8888 0002 A BEGAOR RMB STRT ADDR OF DATA TO MOVE 88258 00O25S 888A 0802 A 8NDADD RMB END ADDR OF DATA TO MOVE 88268 88326B 888C 0801 A OKCTR RMB # OF OK COUNT SAMPLES 03278 80027B 080D 0OO2 A ADRPTR RMB DYNAMIC ADDRESS POINTER 0O280 QQQ28B OQQF 00O2 A BYTPTR RMB STORAGE AREA DNAMIC POINTER 00290 Q0Q29B 081 1 0001 A ZBRCTR RMB COUNTER FOR "0 " BI TS 00308 888388 8812 0001 A ONεCTR RMB COUNTER FOR "1 " BITS 80318 800318 00.3 0001 A LARG8 RMB BYTE TOO LARGE L IMIT 00320 00032B 0814 000- A LOMARK RMB LOU MARK BIT LIMI T 08338 88833B 8815 8881 A HIMARK RMS HIGH MARKS8ITLLIMIT 00340 00Θ34B 0016 0001 A MIDDL8 RMB BYTE IN MIDDLE TOO SMALL 08350 00035B 801 7 0002 A XSAVE RMB X REGISTER OFER . REGISTER 00368 0Θ036B 0019 0002 A XSAVΞ1 RMB 00378 00037B 80 IB 0001 A TPYCTR RUB DECODε ATTEMPT COUNTER 80330 0QΘ33B 08 I C O0O2 A DURA RMB DURATION COUNTER S TORAGE 0039Θ 00Θ39B 08 IE 0001 A M8TεR RMS FREQ CONSTANT STORHGE 00483 88840B OOIF 8001 A LNGFLG RMB LONG INTERROGATE FLAG 00 18 0804 I B 0020 0001 H INTCTR RMB LOCATION FOR INT3VC ONLY 83428 β'30423 0021 8001 A LEVEL RMB STORHGE FOR INTERROGATE LE"E 08438 000478 0022 0001 A AUTOFG RMB FLAG IF SET = AUTO IilTERR 08448 80044B 0023 0002 A RECCTR RMB COUNTS OF TIME ITHOUT CHG 00450 000453 0025 0001 A SYNCFG RMB 08463 30046B 0026 0081 A NONFG RMB 88478 00047B 0827 3001 A CTR14 RMB 08430 00Θ488 0033 0881 H CTR 15 RMB 00498 80349B 3829 000. A CTRALL RMB 08533 QQQ5QB 002A 8801 A BYTSAV RMB 03510 000518 Q82B 0002 H RECTME RMB RECEVE UAIT WO DATA TIME 38528 88052B 002D 8082 H BLNr TN RMB 08530 88Θ53B 002F 0001 A LOUCTR RMB 30548 00854B 0030 0801 A HICTR RMB 30550 Θ3055B 0031 00 1 A METPCT RMB 08568 08856 * 3 • 8578 88357D 0888 DSCT 80538 ΘΘΘ58 XDEF RAUIN. LEV8L 1 , READNG, DIGITS C* 1 _-* _ S i . _QMPI PAGE 882 ACMUX .SA'Θ ACMUX 00590 88059 * 88688 0006 * 000000 83F8 A RAUIN RMB $3FΘ RAU SERIAL DATA STORAGE 00610 øøøSID 03F0 82F8 A L8V8L 1 RMB $2FΘ 1ST LEVEL DEC0D8D DATA 00623 888620 8688 0øEø A READNG RMB - $Eø FINAL BCD DIGIT STORAGF 88621 88863D Θ7C8 8Θ3F A DIGITS RMS $3F 00630 00OS4 * 006 * 40 øøø6 * 5 END TOTAL 8RRQRS 88888— ΘΘΘΘΘ crl ' "5ss i -«- Λ -_- .--r ,: OMPI_ " IPO PAGε 381 INTSVC . SA = Q INTSVC 88818 øθøøl NAN INTSVC ΘO020 00002 *****.** VERSION 85 85 - 81, S U 0 ***.****.*.******* 00Θ30 0OΘΘ3 * 00Θ40 øøøø4 THIS NoauLε is THE INTERRUPT sεRvicε ROUTINE 88858 00O05 FOR THE AC MULTIPLEXOR CARDS. IT IS ENT8R8D ON 38850 Θ0005 THε occuRεNcε OF A LINE SELECTED BY THE NOVA CPU 38373 88887 BEING IN THE OFF-HOOK STA TE, ONCE ENTERED, THIS 88888 βθøøS MODULE SIMPLY TRANSMITS THE OFF-HOOK CODF 38 D8C 88898 88889 TO THE NOVA AND LOCKS UP TH8 MUX SO THAT NO LI WE 88188 88818 ACTIVITY MAY OCCUR UNTIL THE MUX HAS BEEN RESET. 88113 88311 38123 88012 ΘΘ130 08813 OPT LLE=S8, REL 38148 88814? øøøø PSCT 88158 88815 XDEF INTSVC 88158 88816 XRFF PIA, INTCTR SEI NO FURTHER INTERRUPTS CLR INTCTR INIT INTERRUPT LOOP CTR LDAA PIA+2 CLEAR EXISTING FLAG LDAA #$FF DELAY COUNTER D8CA DELAY A MS. OR SO BNB L00P2 TILL DONE LDAA PIA+3 GET FLAG AGAIN ANDA #$8Θ CHECK IF FLAG GOT SET AGAIN BBQ EXIT IF NOT, NOT REAL OFF HOOK INC INTCTR CHALK UP A TRY AT REAL O. H. LDAA #$ø5 # OF TRIES ALLQUED CMPA INTCTR TRIED ENOUGH YET? BNB L0OP1 IF NOT TRY AGAIN LDAA #$18 OFF HOOK CODE ( 33 DECIMAL ) STAA PIA TRANSMIT CODE TO NOVA BRA OFFHK LOCK UP MUX. CL I RE-ENABLE INTERRUPTS RTS HASN ' T REAL R . O . H. END PAGε . øøl PARTBL .SA--0 PARTBL øøølø øøøøl NAM PARTBL 08828 00O02 ******* VFRSION 05 - 11 - 83, 8 U 0 *****.**.******** 80030 08083 * øø04ø 0O004 * THIS MQDULε CONTAINS THE TABLB OF CONSTANTS øøøSΘ 0O005 * usεo BY THε oεcooε MODULE TO SORT OUT THE i 's øøøSø 08006 * AND ø 'S FROM THE RAH DATA COUNTS PRODUCED BY THE 88870 88887 * Rεcεvε MODULE, THE TABLB CONTAINS BNOUGH CONSTANT 08080 88883 * FOR 8 ATTFMPTS AT DECODING THE DATA. EACH LIN8 øøø9ø 80009 * CONTAINS Oøløø øOølø * TH8 CONSTANTS FOR 1 ATT8NPT. CONSTANTS AR8 83118 øøøl l * "LARG8", "SMALL ", AND "NIDDL8" IN LEFT TO RIGHT 88150 Θ8315 OFT LLE=Sø, REL 00150 88ΘI6P øøøø PSCT 08170 88017 XDEF PARTBL, TONTME, UAITMε øølSø øθθlS * 88193 Θ0019 * 30283 00Θ2ΘP 0I3 Q 01 PARTBL NOP 88213 O0021 P 8881 0O2F TQNTNE FD8 $ΘΘ2F, $øøSF 88223 08822P 3885 01FF FOB $81FF, $ø3FF 38238 8Θ823P 8889 04FF FOB $Θ4FF, $ø5FF 38248 88824P 8880 Θ7FF FOB $37FF, $FFFF 88258 88825P 881 1 02FF UAITME FDB $Θ2FF, $ΘFFF 38268 83Θ2SP 0015 1FFF FOB $1FFF, $2FFF 8Θ270 88827P O019 3FFF FDB $3FFF, $4FFF 30280 80328P øø ID FFFF FDB $6FFF, $SFFF 08290 88829 END TOTAL BRRQRS øøøøø — øøøøø OMPI

Claims: AME DED CLAIMS [received by the International Bureau on 08 March.1985 (08.03.85); original claim 2 cancelled; claims 1 , 3, 4, , 24, 25, 26, 28, 43 amended; other claims unchanged (24 pages)] 1.(amended) A multiplexer system for receiving data from a plurality of interrogatable data.transmitters coupled to a plurality of telephone lines comprising: a multiplexer connected to a plurality of telephone lines for coupling the multiplexer system to the plurality of telephone lines; means coupled to said multiplexer for sending at least one distinct interrogation signal via said multiplexer over each of the coupled telephone lines; means directly coupled to said multiplexer for receiving an alternating current representation of the data sent over the coupled telephone lines from each of the plurality of interrogatable data transmitters; means for converting each of the alternating current representations of the data into digital representations. 2. (cancelled) 3. (amended) The multiplexer system in accordance with Claim 1 further including means for multiplexing each of the distinct interrogation signals from a single output circuit directly to a particular one of the plurality of telephone lines. 4.(amended) The multiplexer system in accordance with ISUREAT OMPI Claim 1 further including means for demultiplexing the received alternating current representations from the plurality of directly coupled telephone lines to a single input circuit. 5. The multiplexer system in accordance with Claim 4 in which the alternating current representation from each of the interrogatable data transmitters is a series of pulses of a single audio tone, the pulses having at least two different pulse periods, and, the means for converting the alternating current representation into the digital representation comprises: means for substantially filtering out all but the the series of pulses of the single audio tone received at the single input line; means for deriving a series of positive voltage pulses which are proportional in pulse period duration to the pulse period duration of the series of pulses of the single audio tone; and, means for deriving a series of zero voltage transitions which are proportional in duration to the duration of the transition periods between the pulse periods of the series of pulses of the single audio tone. 6. The multiplexer system in accordance with Claim 5 further including a means for disregarding positive voltage pulses received from the telephone lines during any of the transition periods when the positive voltage pulses have a duration corresponding- to a predetermined positive noise pulse period so that positive noise pulses on the telephone lines do not destroy the ability of the converted digital representations to reflect the proportional pulse periods of the series. of pulses of the single audio tone. 7. The multiplexer system in accordance with Claim 6 further including a means -for disregarding losses in continuity of the positive voltage pulses derived from the series of pulses of the single audio tone during any of the positive voltage pulse periods when the losses in continuity of positive voltage pulses have a duration corresponding to a predetermined negative noise pulse period so that negative going noise pulses on the telephone lines do not destroy the ability of the converted digital representations to reflect the proportional pulse periods of the series of pulses of the single audio tone. 8. The multiplexer system in accordance with Claim 1 in which the means for coupling the multiplexer system to the plurality of telephone lines comprises; means for continuously coupling each of the telephone lines to the multiplexer system by at least one coupling device, the coupling device comprising: means for providing a low impedance path for alternating current signal from between 300 and 3500 Hertz in frequency from at least one of the telephone. lines to the multiplexer system; means for providing a low impedance path for alternating current signals from between 300 and 3500 Hertz in frequency from the multiplexer system to at least one of the telephone lines; means for leaking a direct current voltage from at least one of the telephone lines to the multiplexer system; means for substantially preventing damage to the multiplexer system caused by high voltage conditions on at least one of the telephone lines. 9. (amended) The multiplexer system in accordance with Claim 5 in which the data from each of the interrogatable data transmitters is a utility usage figure, meter identification figure, and at least one sentinel figure, and the converting of the alternating current representions to digital representations further includes: means ' for determining the relative pulse periods of the series of pulses of the single audio tone; means for determining the series of pulse periods which represent a sentinel character from the relative pulse periods of the series of pulses of the single audio tone; means for comparing the relative pulse periods found in least one of the distinguishable sentinel characters to the other relative pulse periods of the series of pulse periods of the single audio tone, and, thus defining the plurality of character periods for the series of pulses of the single audio tone; means for producing digital value signals for each of the character values in the utility usage figure and meter identification figure by comparing the relative pulse periods of the series of pulses of the single audio tone during each of the character periods with a plurality of predetermined patterns of relative pulse periods corresponding to the possible digit values found in a single character period; and, means for storing at least a portion of the digital value signals in a digital value signal storage system. 10.- The multiplexer system in accordance with Claim 1 further including means for communicating the stored digital representations to an external digital interfacing device responsive to a command therefrom. 11. The multiplexer system in accordance with Claim 9 further including means for communicating the stored digital value signals to an external digital interfacing device responsive to a command therefrom. 12. The multiplexer system in accordance with Claim 1 further including a means responsive to trouble-shooting commands from an external digital interfacing device for selecting a particular, non-default voltage level of any of the interrogation signals. 13. The multiplexer system in accordance with Claim 12 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, non-default interrogation signal duration of any of the interrogation signals. 14. The multiplexer system in accordance with Claim 14 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, non-default frequency of the interrogation signal sent over any of the telephone lines coupled to the multiplexer system. 15. The multiplexer system in accordance with Claim 15 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, non-default no-response drop-out time period for any of the telephone lines coupled to the multiplexer system, the no-response drop-out time period being the period that the multiplexer system will wait for data from a non-responsive interrogatable data transmitter after sending an interrogation signal. • 16. The multiplexer system in accordance with Claim 12 further including means responsive to receiving the trouble-shooting command to select the interrogation signal voltage level for communicating the voltage level which activated a non-responsive interrogatable data transmitter selected by the voltage level trouble-shooting command from the external digital interface device. 17. The multiplexer system in accordance with Claim 16 in which at least one of the following conditions is communicated to- the external digital interfacing device responsive to receiving at least one trouble-shooting command, a current voltage level being used to activate the particular interrogatable data transmitter selected by the trouble-shooting command from the external digital interface device, a voltage level which activated the selected non-responsive interrogatable data transmitter, a non-decodable response has been received from the selected interrogatable data transmitter, no response has been received from the selected interrogatable data transmitter and an OFF-HOOK condition has been found on the telephone line coupled to the selected interrogatable data transmitter. 18. The multiplexer system in accordance with Claim 1 further including means for preventing an interrogation signal from being sent over any of the telephone lines which are in an OFF-HOOK condition. 19. The multiplexer system in accordance with Claim 1 further including means for counting the number of occasions when a particular telephone line coupled to the multiplexer system has been in the OFF-HOOK condition during a predetermined period. 20. The multiplexer system in accordance with Claim 8 in which the means for continuously coupling each of the plurality of telephones lines to the multiplexer system when the plurality of telephone lines are single-ended telephone lines comprises:- a first resistor for each telephone line having its first lead connected to the ring wire of the telephone line, and, the central office battery wire of the telephone line connected to an internal ground for the multiplexer system; a second resistor for each telephone line having its first lead connected to the second lead of the first resistor; a capacitor for each telephone line having its first lead connected to the second lead of the first resistor and its second lead connected to second lead of the second resistor; a third resistor for each telephone line having ,its first lead connected to the internal ground of the the multiplexer system and having its second lead connected to the second lead of the second resistor; a first diode for each telephone line having its anode lead connected to the second lead of the second resistor; a first zener diode having its cathode lead connected to the cathode leads of the first diodes and having its anode lead connected to the internal ground, the first zener. diode having its cathode lead connected to a positive voltage source relative to the internal ground; a second diode for each telephone line having its cathode lead connected to the second lead of the second resistor; and, a second zener diode having its anode lead connected to the anode leads of the second diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; the path from the multiplexer system to each of the telephone lines being a combination of the second leads of the second resistors and the internal ground; the path from each of the telephone lines to the multiplexer system being a combination of first leads of the first resistors and the internal ground which is connected to the central office ground wire of each telephone line. 21. The multiplexer system in accordance with Claim 20 in which each of the first resistors has a value of approximately 10 thousand ohms, each of the second resistors has a value of approximately one megaohm, each of the third resistors has a value of approximately 100 thousand ohms, and each of the capacitors has a value of approximately .47 microfarads. 22. The multiplexer system in accordance with Claim 8 in which the .means for continuously coupling each of the plurality of telephones lines to the multiplexer system when the plurality of telephone lines are double-ended telephone lines comprises: a first resistor for each telephone line having its first lead connected to the ring wire of the telephone line; a second resistor for each telephone line having its O.ΛPΪ first lead connected to the second lead of the first resistor; a first capacitor for each telephone line having its first lead connected to the second lead of the first resistor and its second lead connected to second lead of the second resistor; a third resistor for each telephone line having its first lead connected to an internal ground of the multiplexer system and having its second lead connected to the second lead of the second resistor; a first diode for each telephone line having its anode lead connected to the second lead of the second resistor; a first zener diode having its cathode lead connected to the cathode lead of each of the first diodes and having its anode lead connected to the internal ground, the first zener diode having its cathode lead connected to a positive voltage source relative to the internal ground; a second diode for each of the telephone lines having its cathode lead connected to the second lead of the second resistor; a second zener diode having its anode lead connected to the anode leads ' of each of the second diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; a fourth resistor for each telephone line having its OMPI W_PO first lead connected to the tip wire of one telephone line; a fifth resistor for each telephone line having its first lead connected to the second lead of the fourth resistor; a second capacitor for each telephone line having its first lead connected to the second lead of the fourth resistor and its second lead connected to the second lead of the fifth resistor; a sixth resistor having its first lead connected to the internal ground and having its second lead connected to the second lead of the fifth resistor; a third diode for each telephone line having its anode lead connected to the second lead of the fifth resistor; the first zener diode having its cathode lead connected to the cathode leads of the third diodes and having its anode lead connected to the internal ground, the first zener diode having its cathode lead connected to a positive voltage source relative to the internal ground; a fourth diode for each telephone line having its cathode lead connected to the second lead of the fifth resistor; and, the second zener diode having its anode lead connected to the anode leads of the fourth diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; the path from the multiplexer system to each of the telephone lines is the combination of the second leads of the fifth resistors and the second leads of the second resistors; the path from each of the telephone lines to the multiplexer system being the combination of the first leads of the first resistors and the first leads of the fourth resistors. 23. The multiplexer system in accordance with Claim 22 in which each of the first and sixth resistors have values of approximately 10 thousand ohms, each of the second and fifth resistors have values of approximately one megaohm and each of the third, sixth resistors have values of approximately 100 thousand ohms and each of the first and second capacitors have values of approximately .47 microfarads. 24. (amended) A multiplexer system for receiving data from a plurality of interrogatable data transmitters coupled to a plurality of telephone lines and powered therefrom when the telephone llines are in an idle state comprising: a multiplexer; means for coupling the multiplexer directly to the plurality of telephone lines to establish communications paths to any of the coupled lines; means for sending at least one distinct interrogation signal over each of the coupled telephone lines via said multiplexer; means for receiving an alternating current representation of the data sent over the coupled telephone lines from each of the plurality of interrogatable data transmitters via said multplexer, the alternating current representation being a series of dual-tone signals; and means for converting each of the alternating current representations of the data into digital representations. 25. The multiplexer system in accordance with Claim 24 urther including means for storing at least one of the digital representations in a digital representation storage system. *£URE OMPI 26. (amended) The multiplexer system in accordance with Claim 24 wherein said multiplexer communicates each of the distinct interrogation signals from a single output circuit to a particular one of the plurality of telephone lines. 27. The multiplexer system in accordance with Claim 24 - further including means for demultiplexing the received alternating current representations from the plurality of coupled telephone lines to a single input circuit. 28. (amended) The multiplexer system in accordance with Claim 24 in which said interrogatable data transmitters generates a series of dual-tone alternating current representating from the interrogatable data transmitters represent a utility usage figure and a meter identification figure from a utility usage monitor coupled to each the meter interface devices, there being at least twelve distinct dual-tone alternating current representations, the dual-tone alternating current representations representing the following: a digit value between and including 0 to 9, a first framing sentinel and a second framing sentinel. 29. The multiplexer system in accordance with Claim 24 in which the means for coupling the multiplexer system to the plurality of telephone lines comprises; means for continuously coupling each of the telephone lines to the multiplexer system by at least one coupling device, the coupling device comprising: means for providing a low impedance path for alternating current signal from between 300 and 3500 Hertz in frequency from at least one * of the telephone lines to the multiplexer system; means for providing a low impedance path for alternating current signals from between 300 and 3500 Hertz in frequency from -the multiplexer system to at least one of the telephone lines; means for leaking a direct current voltage from at least one of the telephone lines to the multiplexer system; means for substantially preventing damage to the multiplexer system caused by high voltage conditions on at least one of the telephone lines. 30. The multiplexer system in accordance with Claim 24 further including a means responsive to trouble-shooting commands from an external digital interfacing device for selecting a particular, non-default voltage level of any of the interrogation signals. 31. The multiplexer system in accordance with Claim 30 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, -non-default interrogation signal duration of any of the interrogation signals. 32. The multiplexer system in accordance with Claim 31 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, non-default frequency of the interrogation signal sent over any of the telephone lines coupled to the multiplexer system. 33. The multiplexer system in accordance with Claim 32 further including a means responsive to trouble-shooting commands from the external digital interfacing device for selecting a particular, non-default no-response drop-out time period for any of the telephone lines coupled to the multiplexer system, the no-response drop-out time period being the period that the multiplexer system will wait for data from a non-responsive interrogatable data transmitter after sending an interrogation signal. 34. The multiplexer system in accordance with Claim 33 further including means responsive to receiving the trouble-shooting command to select the interrogation signal voltage level for communicating the voltage level which activated a non-responsive interrogatable data transmitter selected by the voltage level trouble-shooting command from the external digital interface device. 35. The multiplexer system in accordance with Claim 34 in which at least one of the following conditions is communicated to the external digital interfacing device responsive to receiving at least one trouble-shooting command, a current voltage level being used to activate the particular interrogatable data transmitter selected by the trouble-shooting command from the external digital interface device, a voltage level which activated the selected non-responsive interrogatable data transmitter, a non-decodable response has been received from the selected interrogatable data transmitter, no response has been received from the selected interrogatable data transmitter and an OFF-HOOK condition has been found on the telephone line coupled to the selected interrogatable data transmitter. 36. The multiplexer system in accordance with Claim 29 further " including means for sensing when any of the plurality of telephone lines is in an OFF-HOOK condition responsive to a drop in the direct current voltage leaked to the tranceiver device. relative to the direct current leaked to the multiplexer system when the telephone lines are in an ON-HOOK condition. 37. The multiplexer system in accordance with Claim 36 further including means for counting the number of occasions when a particular telephone line coupled to the multiplexer system has been in the OFF-HOOK condition during a predetermined period. 38. The multiplexer system in accordance with Claim 29 in which the means for continuously coupling each of the plurality of telephones lines to the multiplexer system when the plurality of telephone lines are single-ended telephone lines comprises: a first resistor for each telephone line having its first lead connected to the ring wire of the telephone line, and, the central office battery wire of the telephone line connected to an internal ground of the multiplexer system; a second resistor for each telephone line having its first lead connected to the second lead of the first resistor; a capacitor for each telephone line having its first lead connected to the second lead of the first resistor and its second lead connected to second lead of the second resistor; a third resistor for each telephone line having its first lead connected to the internal ground of the the multiplexer system and having its second lead connected to the second lead of the second resistor; a first diode for each telephone line having its anode lead connected to the second lead of the second resistor; a first zener diode having its cathode lead connected to the cathode leads of the first diodes and having its anode lead connected to the internal ground, the first zener diode having its cathode lead connected to a positive voltage source relative to the internal ground; a second diode for each telephone line having its cathode lead connected to. the second lead of the second resistor; and, a second zener diode having its anode lead connected to the anode leads of the second diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; the path from the multiplexer system to each of the telephone lines being a combination of the second leads of the second resistors and the internal ground; the path from each of the telephone lines to the multiplexer system being a combination of first leads of the first resistors and the internal ground which is connected to the central office ground of each of the telephone lines. 39. The multiplexer system in accordance with Claim 38 in which each of the first resistors has a value of approximately 10 thousand ohms, each of the second resistors has a value of approximately one megaohm, each of the third resistors has a value of approximately 100 thousand ohms, and each of the capacitors has a value of approximately .47 microfarads. 40. The multiplexer system in accordance with Claim 29 in which the means for continuously coupling each of the plurality of telephones lines to the multiplexer system when the plurality of telephone lines are double-ended telephone lines comprises: a first resistor for each telephone line having its first lead connected to the ring wire of the telephone line; a second resistor for each telephone line having its first lead connected to the second lead of the first resistor; — Ill — a first capacitor for each telephone line having its first lead connected to the second lead of the first resistor and its second lead connected to second lead of the second resistor; a third resistor for each telephone line having its first lead connected to an internal ground of the the multiplexer system and having its second lead connected to the second lead of the second resistor; a first diode for each telephone line having its anode lead connected to the second lead of the second resistor; a first zener diode having its cathode lead connected to the cathode leads of the first diodes and having its anode lead connected to the internal ground, the first zener diode having its cathode lead connected to a positive voltage source relative to the internal ground; a second diode for each telephone line having its cathode lead connected to the second lead of the second resistor; a second zener diode having its anode lead connected to the anode leads of the second diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; a fourth resistor for each telephone line having its first lead connected to the tip wire of one telephone line; a fifth resistor for each telephone line having its first lead connected to the second lead of the fourth resistor; a second capacitor for each telephone line having its first lead connected to the second lead of the fourth resistor and its second lead connected to the second lead of the fifth resistor; a sixth resistor for each telephone line having its first lead connected to the internal ground and having its second lead connected to the second lead of the fifth resistor; a third diode for each telephone line having its anode lead connected to the second lead of the fifth resistor; the first zener diode having its cathode lead connected to the cathode leads of the third diodes and having its anode lead connected to the internal ground, the first zener diode having its cathode lead connected to a positive voltage source relative to the internal ground; a fourth diode for each telephone line having its cathode lead connected to the second lead of the fifth resistor; and, the second zener diode having its anode lead connected to the anode leads of the fourth diodes and having its cathode lead connected to the internal ground, the second zener diode having its anode lead connected to a negative voltage source relative to the internal ground; the path from the multiplexer system to the telephone lines is the combination of the second leads of the fifth resistors and the second leads of the second resistors; the path from the telephone line to the multiplexer system being the combination of the first leads of the first resistors and the first leads of the fourth resistors. 41. The multiplexer system in accordance with Claim 40 in which each of the first and sixth- resistors have values of approximately 10 thousand ohms, each of the second and fifth resistors have values of approximately one megaohm and each of the third, sixth resistors have values of approximately 100 thousand ohms and each of the first and second capacitors have values of approximately .47 microfarads. 42. The multiplexer system in accordance with Claim 28 further including means for communicating the digit values received to an external digital interfacing device responsive to a command therefrom. 43. (amended) .A ' method for receiving data from a plurality of interrogatable data transmitters coupled to a plurality of telephone lines comprising: continuously supplying operating power to said interrogatable data transmitters over said telephone lines; selectively sending at least one distinct interrogation signal over each of the coupled telephone lines; receiving an alternating current representation in the telephone voice band of the data sent over the coupled OMPI WiPO telephone lines from each of the plurality of interrogatable data transmitters upon interrogation; and converting each of the alternating current representations of the data into digital representations for processing. 44..The method of receiving data in accordance with Claim 43 in which the alternating current representation from each of the interrogatable data transmitters is a series of pulses of a single audio tone, the pulses having at least two different pulse periods, and, the step of converting the alternating current representation into the digital representation comprises: filtering the series of pulses of the single audio tone received at the single input line; deriving a series of positive voltage pulses which are proportional in pulse period duration to the pulse period duration of the series of pulses of the single audio tone; and, - deriving a series of zero voltage transitions which are proportional in duration to the duration of the transition periods between the pulse periods of the series of pulses of the single audio tone. 45. The combination in accordance with Claims 1 and 25 including means responsive to an unacceptable signal from an interrogated data transmitter for increasing the level of -the interrogation signal for that data transmitter at the next interrogation thereof; and means for registering the data transmitter as inoperative upon the failure to receive data therefrom in response to such subsequent interrogation. 46. The combination in accordance with Claim 25 wherein said increasing means increases the level of interrogation signal sequentially to higher levels. 47. The combination in accordance with Claim 26 including means for setting the normal level for interrogation at the lowest level for which a usable response has been received from a data transmitter. 48. The combination in accordance with Claim 26 wherein said increasing means increases the level of interrogation signal in stepped increments. 49. The combination in accordance with Claim 28 including means for storing line condition information as a function of the lowest step level at which usable data is received from each data transmitter. 50. The combination in accordance with Claim 29 including means for recording a faulty line if no usable data is detected after interrogation at the highest incremental step level of said interrogation signal.

Inventors: COSGROVE JOHN, OLIVER STEWART W, COSGROVE, JOHN, OLIVER, STEWART, W.
Applicants: INT TELDATA II CORP, INTERNATIONAL TELDATA II CORPORATION
Application year: 1984
Main classification: H04J3
IPC codes: H04M11