DISTRIBUTED SWITCHING TELECOMMUNICATIONS SYSTEM

Abstract: A system that interconnects several units such as telephones to a transmission media such as a coaxial cable (11, 12). An interface (20) between the cable and the phones, divides the cable into channels and interconnects the phones to the different channels. This Distributed Switching System (DSS) for phones eliminates the need for the long pair of wires and the central switch in a telephone system.

Description: DISTRIBUTED SWITCHING TELECOMMUNICATIONS SYSTEM BACKGROUND OF THE INVENTION This invention relates to a telecommunications system for voice or data to replace. the lines of a telephone system. Prior art telephone systems utilize a pair of wires from each telephone set to a central office that connects one telephone to another using a central switch. These prior art telephone sys¬ tems require expensive cables running long distances and expen¬ sive support equipment and a central switch that interconnects the telephones. Further, these cables require special care because of their susceptibility to adverse weather conditions. My invention embodies an electronic circuit adapted to be connected to a cable and to a plurality of telephones. The invention allows each telephone to communicate with the others in the same cable without the use of long pairs of wires and without the use of central office equipment. Central office equipment would be used only if a call is for a telephone not connected to the cable and coming from another office. My sys¬ tem reduces the number of telephone poles substantially that would be required to support the same number of telephones . The cable such as a coaxial cable has a wide band¬ width. It can accommodate several signals at the same time in a concept well known in the industry, called Frequency Division Multiplexing (FDM) or Time Division Multiplexing (TDM) . This concept has been used for many years to transmit different sig¬ nals simultaneously over the same cable from one point to another. The cable is divided into channels and each signal uses a channel. My invention uses these well known techniques, but it dynamically allocates those channels (created in FDM or TDM) to different users. The essence of my invention is in the inter¬ face electronics connected between the cable and each telephone set. The board allows the phone to select a channel available for use by the initiating phone (transmitting) and send a signal to the telephone (receiving) to use the same channel. This in¬ formation is sent in a special data signaling channel that every telephone is equipped with. The board has a transmitter and a receiver capable of changing their frequencies using a Phase Lock Loop (PLL) . These frequencies correspond to the different channels allocated in the cable. A microprocessor in the board SUBSTITUTE SHEET changes the transmitting and receiving frequencies. The microprocessor further selects an empty channel for the call. One of the channels, a data signaling channel, is used as a com¬ munications channel among all telephone boards and the central office. When a user places a call the microprocessor in the associated board with that phone selects a channel pair and com¬ municates through the data signaling channel to all the tele¬ phones which the communications channel has selected. All tele¬ phone boards update the channel ' s free status in order to prevent any other telephone from using it. The calling telephone sends its number, the called telephone number and the selected channel. The called telephone replies back as to whether it is busy or not. If it is not busy, the communication is established. If the call is for a telephone outside of the cable, a PC board in the central office connects the telephone to and. outside the telephone network. My invention broadly comprises a telecommunication system for voice (telephones), data or video using a distribu¬ tive switching technology (DST). BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a schematic of single phone interconnected to a board connected to a coaxial cable; Figures 2a and 2b are schematics of a dual cable tree topology; Figure 3 is a block diagram of an interconnected board; Figure 4 is an illustration of a frequency band plan; Figures 5 and 6 are illustrations of a communications forma ; and Figure 7 is a flow chart of the calling and called telephone sequence. DESCRIPTION OF THE PREFERRED EMBODIMENTS) In Figure 1 a telephone 2 is connected to an interconnect board 4 which in turn is connected to a coaxial cable 6. The phone 2 is a standard telephone commonly in use today having the standard two-wire or two line. The cable 4 is SUBSTΪTUTE SHEET standard material having a conductor line surrounded by a con¬ ducting tube held in place by insulators. Referring to figure 2 an analogue version of a dis¬ tributed switching network of my invention is shown generally at 10. It comprises coaxial cables 11 and 12 to transmit and to receive respectively. The coaxial cables 11 and 12 have a fre¬ quency allocation plan as shown in figure 4, which allows lOKhz per channel. Each telephone conversation requires two channels. The call originator transmits on an odd channel and the called phone responds on an even channel. A repeater amplifier as com¬ monly known in the art, such as used with a Cable TV distribu¬ tion system, is placed in line in the coaxial cables. A dead end 14 is formed and interconnects the transmit and receive cables in the central office such that what is transmitted by all telephones in service in one direction will be received by all telephones through the other cable in the other direction. Telephone poles 15 across the city or the country sup¬ port the cables and the boards. A Directional coupler 18 con¬ nects branch coaxial cables 16 and 17 to the main cables 11 and 12. An electronic printed circuit board 20 connects each telephone pair 21 to the coaxial cables 11 and 12 (or 16 and 17). The coaxial cables are each held by a steel cable (not shown) connected between the poles. The steel cable has plastic hangers (or other suitable material) that holds the coaxial cables in place. The steel cable is used to transmit an elec¬ trical ground for all boards plus a negative voltage for the system. At the Central office there exists a PC board 22. The boards are connected to the coaxial cable that runs from the dead end 14 to a terminating register 19. Each board 20 connects one telephone to the outside office if the call is to go to another area. Referring to Figure 3 the PC board 20 comprises a hy¬ brid IC 30 such as a Motorola MC3419. This IC 30 isolates the signal received by the phone from the signal transmitted by the phone. The IC 30 is joined to a REC expandor 43, a transmit compandor 32 and a microprocessor 35. C.Ϊ f S5"S'T'Sτrn \~~--~ t~* ~J ~~ --*--- ~~-.*-*t >~m~ _ . . g ^ rJ≥iS T The compandor 32 such as an Exxar XR2216 compresses the signal and increases low level signals such as a soft talker user and ^ reduces the level talker user signal. The VCO - Modulator 33 such as an Exxar XR 205 is a multiple use device that covers a wide range of frequencies, modulates them in AM, DSB or FM and provides a sinusoidal out¬ put. A Phase lock loop (PLL) 34 such as Motorola MC 145106 is a feedback loop that generates a correction voltage if the internal reference counter differs from the microprocessor se¬ lected number. This IC 34 forces the VCO 33 to be in the desired frequency. An oscillator 31 such as National 555 or 556 sends a dial tone or a ring back tone as the microprocessor requests it. A Frequency Shift Key 36 (FSK) such as Exxar XR-2206 function generator transmits microprocessor information (such as telephone called, telephone status, etc.) to all other tele¬ phones and to the Central Station in the data signaling channel. An FSK Receiver 38 such as EXXAR XR-2211 receives the FSK signal and decodes it. An Amplifier 40 such as National LM 324 amplifies the receive signal from the coaxial cable. A balance mixer such as Motorola MC 1496 combines the Receive Channel VCO 44 frequency and the incoming frequency. A low Pass Filter (LP) such as Two LM324 operational amplifiers is used as an active filter. A limiter and discriminator such as Motorola MC 3357 demodulates the signal coming from the filter. Associated with this circuit is an automatic gain control (AGC) circuit that feedbacks a control signal to the receiver amplifier 40. The AGC comprises of two transistors such as AN 2222. ©An expandor 43 that expands the compressed signal to the normal user amplitude range. A signal EM 50 that is used only in the PC board to interface with another telephone truck. Those wires are not used when the PC board is functioning as a telephone interface. COMMUNICATION FORMAT In the preferred embodiment the communication will be a series of pulses in the data signaling channel. This is made in a frame that consists of 1 - SYNC PULSE (Code FO in HEX) one Byte (see Figure 5) 2 - Identification ID in HEX. One Byte IDS - FD IDR - FB IDL - FC IDD - FA ASK - FE REPLY - F9 3 - My telephone number in Binary one Byte per number. Seven Bytes. 4 - The Called Number in Binary one Byte per number. Seven to 11 Bytes. (for long distance call Example 1-617-555-1212) 5 - Channel Pair Selects in Binary (0-255 Decimal. One Byte. ) 6 - Postamble One Byte Check sum to verify information. The microprocessor 35 for the preferred embodiment is the INTE 8748 available from Intel Corporation, Santa Clara, California. Figure 3 shows the microprocessor 35 interconnec¬ tions. The control of the microprocessor 35 is accomplished by instructions. The instructions are written in terms of the particular mode of operation desired. The microprocessor thus has stored in its memory the programs and routines corresponding to each mode of operation. Any standard computer language such as "C" or "Assem¬ bler" consistent with the capabilities of the microprocessor can be used for the instructions. All subroutines are not described in details since they can be written upon a particular microprocessor being utilized, the computer language, etc. Pro¬ grams and instructions described below are put in term of struc¬ tural flow. When necessary for the purposes of the invention, the individual programs are described. The source code for the programs is set forth below. All controls initiate and return to and from the main program depending upon the mode of operation. 1. BEGIN This is a housekeeping routine. It clears all regis¬ ters, sets Interrupt Enable, stack pointer and the ASK FLAG. This ASK FLAG will allow the ASK FLAG routine to send a status request signal to see which channel is available. 2. ON HOOK If the telephone is on the hook go to calling FLAG routine (Step 14). If not continue. 3. SET DIAL TONE 4. WAIT FOR FIRST PULSE, IF SUBSCRIBER HANGS UP PHONE GO TO CALLING. 5. DISCONNECT DIAL TONE This routine disconnects the dial tone and resets the temporary register that stores the dailed digit to zero. Set the digit pointer to zero. 6. CHECK FOR MORE THAN FORTY MILLISECOND BUT LESS THAN EIGHTY, IF NOT GO TO CALLING. This routine checks if a pulse was sent or if the telephone was hung up. This starts pulse count logic. 7. INCREMENT TEMPORARY REGISTER This is part of the pulse count routine. 8. IF LOW LESS THAN 60 MS. GO TO 6. This checks the Break of the dialing pulse, if longer than 60 MS it means that it was the last pulse in the digit chain if not it goes back to step 6 to count. 9. MOVE TEMPORARY REGISTER TO BUFFER. 10. CLEAR TEMPORARY REGISTER. 11. INCREMENT POINTER This indicates in which dialing digit we are. 12. LAST DIGIT TO BE DIALED CONTINUE IF NOT GO TO STEP 6. 13. SET THE CALL FLAG. 14. CALLING FLAG SET? GO TO REC IDS ROUTINE IF FLAG IS NOT SET. If the CALL FLAG IS SET means that we want to place a call. This routine starts the sequence. 15. BUS REQUEST This routine waits until the telephone receives the TOKEN to start transmitting. This TOKEN is the opportunity for the PC oard to start a transmission of information in the DATA SIGNALING CHANNEL. 16. SELECT CHANNEL FOR VOICE COMMUNICATION This routine goes to the channel free map and picks on empty channel. Then it sets the PLL to the selected channel frequency. This will be an ODD channel. 17. SELECT THE IDS CODE TO TRANSMIT This code will tell all the telephones in the sysem that this is a call. 18. SEND FRAME See Figure 5 for a frame signal to be sent. 19. Reset CALL FLAG This reset of the frag set at step 13, will indicate that the telephone call has been placed. 20. Delay This will wait until the called telephone or selected outside link answer with IDR or Receive acknowledge. 21. If 'REC IDR FLAG" set go to step 26. This routine checks if the other telephone or the truck has sent the Buzzy tone or ringing tone. If the IDR Flag is set it will go to a Local ring routine if no it will go to a buzzy tone. 22. SET THE BUZZY TONE OSCILLATOR. 23. IF THE CALLER UNIT IS "OFF HOOK" GO TO 22. This loop keeps a buzzy tone until the user hangs up his telephone. 24. SEND "IDL" FRAME TO THE SIGNALING CHANNEL. This routine is sent to "tell" to the whole sysem that the selected channels are not used anymore. This routine fol¬ lows the steps below. - wait for a TOKEN - transmit frame set free up my channel (the one selected for one call) reset my "IDR" Flag SUBSTITUTE SHEET - update my channels status flags. 25. GO TO "RECIDS". STEP 33. This finishes the transmission cycle we then go to the REC IDS routine that will check if any user or trunk has sent an IDS frame with my number on it. 26. GENERATE LOCAL RING 27. IF MY "IDD" FLAG IS SET GO TO 30. The IDD Flag indicates that we receive a frame with an IDD code and my telephone number on it. This means that the telephone that I am calling on receives the ring, and the sub¬ scriber on the other end picks up his telephone and his unit sends me the IDD frame for me to stop my local ring. 28. IF THE SENDING TELEPHONE IS OFF HOOK GO TO STEP ,26. 29. SEND "IDL" ROUTINE. This step means that the sending telephone was hung up because the receiver did not answer and the sender decided to hang up. The function of this routine is explained in step 24. 30. STOP LOCAL RING. 31. IF THE ORIGINATOR "OFF HOOK" THEN WAIT. The microprocessor stays in this loop as long as the conversation goes on. Once the originator (my telephone) hangs up it jumps to the next step. 32. Send "IDL" to all telephones. See explanation in step 24. RECEIVING CALL SUBROUTINES 33. RECIDS - IF I DID NOT RECEIVE AN IDS FLAG GO TO 49. 34. SET RECEIVE AND TRANSMIT CHANNELS. Now we are receiving a call, the sender sends a frame with an IDS code, his number, my number and channel selected. With this information a channel opposite to his is selected. We will receive in an ODD channel and transmit. End. 35. SET THE RINGER ON. This is my real ring because I am receiving now. In the sender microprocessor what is happening is what we saw before when we were transmitting. 36. SEND "IDR" FRAME. This frame is shown in Figure 5. This will activate the local ring at the send PC board. The send microprocessor will be executing steps 26 to 28. 37. IF I OFF HOOK THE TELEPHONE GO TO 43. 38. IF I DO NOT RECEIVE "IDL" FROM SENDER GO TO 37. The receiver microprocessor is still in this loop until I pick up my telephone (the RING STOP) or if the sender hangs up I receive IDL and my ring stops. Also, I will free up the channels and update my channel maps. 39. STOP RINGING. 40. FREE UP CHANNEL. 41. SEND "IDL." This frame will be sync byte, IDL code, my number, the caller number, channel number and check code. 42. RESET "IDL" FLAG. This Flag was set by my interrupt routine when we re¬ ceived it from the sender. 43. STOP RINGER. 44. SEND "IDD" FRAME This will stop the local ringer in the sender. 45. WAIT UNTIL MY TELEPHONE (THE RECEIVER) IS ON HOOK. 46. FREE UP CHANNELS. 47. SEND THE IDL CODE. Same as step 41. 48. RESET "IDS" FLAG. 49. IF ASK FLAG IS NOT SET GO TO 2. This Flag is a status request from another telephone to update its channel map. Normally the central office answers it. If not, any telephone could answer it after a Delay. 50. DELAY The telephone with the TOKEN will answer after this delay, this provides the central office the opportunity to answer first. 51. IF ASK FLAG IS NOT SET GO TO 2. Usually the central office will reply and the program goes from 51 to step 2. SUBSTITUTE SHEET 52. RESET "ASK" FLAG. 53. SEND CHANNEL STATUS. This will happen at TOKEN time. This prevents more than one telephone reply at the same time. When reply is re¬ ceived, all telephones reset the ASK flag automatically. 54. GO TO 2. INTERRUPT ROUTINE This routine is activated every time that a signal is received in the data signaling channel. The purpose of this routine is to receive the transmitting frame and: - verify the validity of the data - store the calling number in the microprocessor memo¬ ry - verify if called number - identify the selected voice channel number and store it in memory - identify the code (ID) and set the flags. Those flags are going to indicate to the microprocessor which routine to execute .. IDS Flag this indicates that a telephone is sending a calling signal. If this signal is received with my number I set the IDS Flag. IDR Flag If this signal is received with my number on the frame, it indicates that my call was received when I send the IDS signal, and the other telephone is ringing. IDD Flag This indicates that the ringing telephone (the one receiving a call) was picked up. The caller telephone would stop the ring back signal. .. IDL Flag This indicates that the telephone finished its call and this free up the voice channel . .. ASK FLAG This flag indicates that a telephone wants to know the voice channels free status map. SUB . . REPLY FLAG This flag indicates that the signal being received is a bit string of the voice channel status . One bit per voice channel. One indicates free and zero indicates busy. STEPS IN THE INTERRUPT ROUTINE INT 1 - SYNC This identifies the first byte transmitted to see if it is an FO HEX (the first byte signal) INT 2 - SORT IF ID EQUAL TO IDS JUMP TO STEP INT 8 INT 3 - IF ID BYTE EQUAL TO IDR JUMP TO STEP INT 9 INT 4 - IF ID BYTE EQUAL TO IDL JUMP 10. INT 5 - IF ID BYTE EQUAL TO IDL JUMP TO INT 11. INT 6 - IF ID BYTE EQUAL TO ASK JUMP TO INT 12. INT 7 - IF ID BYTE EQUAL TO "REPLY" JUMP TO INT 13. INT 8 - IDS IF MY NUMBER IS RECEIVED SET THE IDS FLAG IF NOT JUMP TO INT 14. INT 9 - IDR IF MY NUMBER IS RECEIVED SET THE IDR FLAG IF NOT JUMP TO INT 14. INT 10 - IDD IF MY NUMBER IS RECEIVED SET THE IDD FLAG IF NOT JUMP TO INT 14. INT 11 - IDL IF MY NUMBER IS RECEIVED SET THE IDL FLAG IF NOT JUMP TO INT 14. INT 12 - ASK - IF MY NUMBER IS RECEIVED SET THE ASK FLAG. IF NOT JUMP TO STEP INT 14. INT 13 - REPLY IF MY NUMBER IS RECEIVED. SET THE REPLY FLAG IF NOT JUMP TO INT 14. INT 14 - DIAGNOSTIC. INT 15 - RETURN. SU TELECOMMUNICATIONS 1 • * 2 ?TITLE(TE-..E MJNICΑTIONS) 3 $0BJECT(A:JOSE,HEX) 4 $PAGEWIDIH(132) 5 0000 6 TT1 EQU 00 :0-100 0001 7 TT10 EQU 01 :[1-100](STEP 10) 0062 8 TT50 EQU 98D :128-30 0071 9 TT51 EQU 113D :128-15 001C 10 TT52 EQU 28D :128-45,128-100 OOFF 11 TT8 EQU OFFH OOFF 12 TT9 EQU OFFH OOOC 13 TT40 EQU 12D :3072, (3101) 0074 14 TTX EQU 116D :256-140 000A 15 TTM EQU OAH ;QA-101 16 / LDELAY f3+(4R*3)+5] 17 / DELAY (20*R3)+2 0000 15 18 DIS I 0001 0405 19 JMP BEGIN 00034447 20 JMP INTE 0005 C7 21 BEGIN: MOV A,PSW ;SET STK P03-NTER 0 0006 53F8 22 ANL A,#CF8H ;A=XXXXXOCO 0008 D7 23 MOV PSW,A 0009 35 24 DIS TCNTI OOOA 8903 25 ORL PI,#03 OOOC E5 26 SEL MEO GOOD C5 27 SEL RBO CODE B91F 28 MOV R1,#1FH ;SET FLA POINTER 31 00108807 29 ORL BUS,#07H ;ENABLE PO E O l 2 00128902 30 ORL PI,#02 00142308 31 MOV A,#08H ;ENABLE REPLY FLA TO 0016 Al 32 MOV R1,A ;ACCEPT STAT, RET 0017 BDFE 33 MOV R5,#OFEH ;SEND ASK 0019 3485 34 CALL BUSREO 001B 34B7 35 CALL IDSEND 001D 05 36 EN I ■ Om ~~ T=80 MICROSEC SUBST/TUTE OOIE B100 37 MOV R1,#00 CLEAR ALL FLAGS 002008 38 GNHOOK: IN A,PO READ ON INPUTS 0021 5301 39 ANL A,#01H ; IF IT IS H JUMP, IF L 0023 9661- 40 JNZ CALING 0025 08 41 IN A,PO ; SET TONE GEN (PO-4) 0026430F 42 ORL A,#OFH j OUT AND SEND H TO 002890 43 OUTL PO,A IN LINES ON PO, SET DI 0029 B818 44 MOV RO,#24D SET POINTER TO 24 002B 08 45 ON: IN A,PO WAIT FOR H PULSE 002C 5301 46 ANL A,#01 IT'S WILL INDICA¬ 002E C62B 47 JZ ON TE DIALING OR HAN 0030 08 48 IN A,PO DISCONNECT TONE 0031 53F7 49 ANL A,#OF7H 0033 90 50 CUTL PO,A 0034 BCOO 51 MOV R4,#00 • SET TEMP TO 0 0036 2362 52 H40: MOV A,#TT50 • CHK FOR 40MS H 003862 53 MOV T,A 003945 54 STRT CNT 003A 42 55 H40C: MOV A,T 003B F23A 56 JB7 H40C •WAIN TIL 40MS H 003D 08 57 IN A,PO 003E 5301 58 ANL A,#01 0040 C650 59 JZ L60 • IF L CHK 40MS L 0042 2371 60 MOV A,#TT51 ;IF H EXT 20MS 004462 61 MOV T,A ;THEN EXIT 0045 45 62 STRT CNT 004608 63 H20: IN A,P0 ;IF IT IS L DURIN 0047 5301 64 ANL A,#01 ;THE 20 MS IT CONT 0049 C650 65 FZ L60 ;TO 40MS L 004B 42 66 røv A,T ;IF H EXTEND EXIT 004C F26D 67 JB7 CALING 004E 0446 68 JMP H20 0050 IC 69 L60: INC R4 ;DIGIT COUNT 0051 231C 70 MOV A,#TT52 ;SET TIMER FOR MAX L 0053 62 71 MDV T,A 005445 72 STRT CNT 0055 08 73 L60C: IN A,P0 ;CHK IF H, JMP TO 0056 5301 74 ANL A,#01 ;NEXT PULSE COUNT SUBSTITUTE SHEET 0058 9636 75 JNZ H40 005A 42 76 MOV A, T • CONT IF L MAX 60 M 005B F25F 77 JB7 MAXL • BIT 7 WILL BE H 005D 0455 78 JMP L60C • TILL 60MS, WILL L 005F FC 79 MAXL: MOV A, R4 • MOV TEMP TO BUFFER 0060 AO 80 MOV ED,A 0061 18 81 INC RO • INC POINTER 0062 748D 82 CALL DEBUG1 0064 23E1 83 MOV A, #0E1H • POINTER MAX 7, ADD 0066 68 84 ADD A, EO COMP ADR (RO+D+A 0067 962B 85 JNZ ON • BACK TO NEXT DIGIT 0069 Fl 86 MOV A, Rl •SET CALL FLA 2A 006A 4302 87 ORL A, #02 006C Al 88 MOV R1,A 006D Fl 89 CALING: MOV A, Rl 006E 5302 90 ANL A, #02 0070 C6F8 91 JZ RECIDS 0072 3485 92 CALL BUSREQ 0074 BFOO 93 MOV R7, #00 • SEL CH #, RO-CH 0076 B81F 94 MOV R0, #31 • GEOUP POINTER 0078 BEOO 95 MOV R6, #00 • R6 CH# IN A GROUP 007A 18 96 FRAME3: INC EO 007B FO 97 MOV A, RO • IF ALL BZ, READ NE 007C 17 98 INC A • GR AFTER CARRY TIL 007D F67A 99 JC FRAME3 • BUG 007F FO 100 MOV A, RO •READ LAST GR AGAIN 0080 IE 101 OONT: INC R6 • INDIC CH# IN GR 0081 67 102 RRC A 0082 F680 103 JC CONT 0084 F8 104 MOV A, RO ■ MOV GR# TO ROTATE 0085 E7 105 EL A • GR# BY 8, RO-GR# 0086 E7 106 EL A 0087 E7 107 EL A 0088 E7 108 EL A 0089 6E 109 ADD A, R6 008A AF 110 MOV R7,A • CANAL ABIERTO 008B 3A 111 PLL: CUTL P2,A • CH-PLL 008C 08 112 IN A, PO • R-0 SUBSTITUTE SHEET 008D 53DF 113 ANL A,#ODFH 008F 4340 114 ORL A,#40H ; T-l 0091 90 115 OUTL PO,A 0092 BDF • * D 116 MOV R5,#0FDH 009434B7 117 CALL IDSEND 0096 Fl 118 MOV A, Rl ; RESET CALL FLA 0097 53FD 119 ANL A,#OFDH 0099 Al 120 MOV R1,A 009A BBFF 121 MOV R3,#0FFH 009C 5433 122 CALL LDELAY ; WAIT FOR ID-R FLA 009E 5433 123 CALL LDEIAY ; NON BZ SIG 15+15MS OOAO Fl 124 RECFLA: MOV A, Rl ; IDR=H/TIMBRE 00A1 F7 125 RLC A 00A2 F6BF 126 JC RECTIM 00A48808 127 BZTCNE: ORL BUS,#08 j SET H BIT 3 00A6 BBFF 128 MOV R3,#0FFH 00A85433 129 CALL LDELAY OOAA 98F7 130 ANL BUS,#0F7H OOAC BBFF 131 MOV R3,#0FFH OOAE 5433 132 CALL LDELAY OOBO 08 133 IN A,PO 00B1 5301 134 ANL A,#01 •H-ENGANCHO 00B3 C6A4 135 JZ BZTONE • IF ON L JUMP 00B5 3485 136 IDLXMIT: CALL BUSREO 00B7 BDFC 137 MOV R5,#0FCH 00B934B7 138 CALL IDSEND OOBB 5419 139 CALL RESETL • RESET P L, IDR,D OOBD 04F8 140 JMP RECIDS ■ REC REP,FLAGS OOBF 08 141 RECTIM: IN A,PO • TIMBRE LOCAL 5H OOCO 4310 142 OEL A,#10H • TIM REAL 5H+1H 00C290 143 OUTL PO,A 00C3 BBFF 144 MOV E3,#0FFH 00C5 5433 145 CALL LDELAY 00C75433 146 CALL LDELAY 00C908 147 IN A,PO OOCA 53EF 148 ANL A,#OEFH OOOC 02 149 OUTL BUS,A OOCD BBFF 150 MOV E3,#0FFH SUBSTITUTE SHEET OOCF 5433 151 CALL LDELAY 00D1 5433 152 CALL LDELAY 00D3 Fl 153 MOV A, Rl ?REC IDD FLA 00D453 •4 * 0 154 ANL A,#40H 00D696E7 155 JNZ CORTA 00D808 156 IN A,PO ENGANCHO 00D95301 157 ANL A,#01H OODB C6BF 158 JZ RECTIM ;'NO OODD 3485 159 CALL BUSREQ ;SI OODF BDFC 160 MOV R5,#0FCH 00E134B7 161 CALL IDSEND 00E35419 162 CALL RESETL ;RESET PLL,IDD,REC 00E504F8 163 JMP RECIDS 00E77497 164 CORTA: CALL DEBUG 00E998EF 165 ANL BUS,#OEFH ;CORTA TIM LOCAL OOEB 08 166 IN A,P0 WAIT TILL HANG OOEC 5301 167 ANL A,#01 OOEE C6E7 168 JZ CORTA ;NO OOFO 3485 169 CALL BUSREQ ;SEND IDL 00F2 BDFC 170 MOV R5,#0FCH 00F434B7 171 CALL IDSEND 00F65419 172 CALL RESETL 00F8 Fl 173 RECIDS: MOV A, Rl ;IDS FLA B=YES 00F95304 174 ANL A,#04 ;L=NO-EXIT OOFB 96FF 175 JNZ ASK IMPLY R7 READ AFTE OOFD 2450 176 JMP ASKFLA OOFF FF 177 ASK: MOV A,R7 rIDS, CH# REC 0100 3A 178 OUTL P2,A ?SET PLL 010108 179 IN A,P0 01024320 180 ORL A,#20H ;SET R=l 010453BF 181 ANL A,#OBFH ;SET T=0 01064310 182 ORL A,#10H ;SET TIMBRE 010802 183 OUTL BUS,A 0109 3485 184 CALL BUSREQ ;FORM FRAME IDR 010B BDFB 185 MOV R5,#OFBH 010D 34B7 186 CALL IDSEND 010F 08 187 DESC1 : IN A,PO ;DESCUELGA 01105301 188 ANL A,#01 TUTE SHEET 0112 C634 189 JZ LOADD ;L-DESCUEL, H-ENGA 011408 190 IN A,PO ;TIMBRE ON 01154310 191 ORL A,#10H 011702 192 OUTL BUS,A 0118 BBFF 193 MOV R3,#TT8 011A 34AB 194 CALL r-ELAY 011C 08 195 IN A,PO ;TIMBRE OFF 011D 53EF 196 ANL A,#OEFH 011F 02 197 OUTL BUS,A 0120 BBFF 198 MOV R3,#TT9 012234AB 199 CALL DELAY 0124 Fl 200 MOV A, Rl ;REC IDL FLA, L=ΦTO 01255301 201 ANL A,#01 ;H-Y, EL TIM SE AP 0127 060F 202 JZ EESC1 ;GA EN OIOLO OFF 0129 2300 203 MOV A,#00 ; ESET PLL 012B 3A 204 OUTL P2,A 012C 3485 205 CALL BUSREQ ;LQAD IDL 012E BDFC 206 MOV R5,#0FCH 0130 34B7 207 CALL IDSEND 0132244C 208 JMP RESIDS ;RESET IDL S FLA 01343485 209 LOADD: CALL BUSREQ .LOAD IDD 0136 BDFA 210 MOV R5,#0FAH 0138 34B7 211 CALL IDSEND 013A 08 212 IN A,P0 013B 53EF 213 ANL A,#0EFH 013D 02 ' 214 OUTL BUS,A 013E 08 215 ENGAN: IN A,PO 013F 4301 216 ORL ,A#01 0141 C63E 217 JZ ENGAN ;L-NO H-Y 0143 2300 218 MOV A,#00 01453A 219 OUTL P2,A ;LIBERO PLL 0146 3485 220 CALL BUSREQ 0148 BDFC 221 MOV R5,#0FCH 014A 34B7 222 CALL IDSEND 014C Fl 223 RESIDS: MOV A, Rl ;RESET IDS.IDL 014D 53FA 224 ANL A,#0FAH 014F Al 225 MOV R1,A 0150 Fl 226 ASKFLA: MOV A, Rl 01514310 227 ORL A,#10H 0153 9657 228 JNZ TEMP2 01550420 229 JMP ONHOOK 0157 BgOl 330 TEMP2 : MOV R3,#TT10 015934AB 231 CALL DELAY ;TIEMPO PARA CCNTE! 015B Fl 232 MOV A, Rl; ;DIFER FOR USUARIO 015C 4310 233 ORL A,#10H 015E 9662 234 JNZ TEMPI ;NO ASK FLA 01600420 235 JMP ONHDOK 0162 Fl 236 TEMPI : MOV A, Rl ;Y=RESET ASK FLA 0163 53EF 237 ANL A,#OEFH ;AND SEND STATUS 0165 Al 238 MOV R1,A 0166 3485 239 CALL BUSREQ ;SEND STATUS 016823F0 240 MOV A,#OFOH ;SYNC 016A 34E2 241 CALL FRAME 016C 23F9 242 MOV A,#OF9H 016E 34E2 243 CALL FRAME 0170 B820 244 MOV RO,#32 0172 FO 245 REP: MOV A, RO ;STAT IN 8 BIT BLOC 0173 34E2 246 CALL FRAME 0175 18 247 INC RO 0176 F8 248 MOV A,RO 017703C0 249 ADD • A,#192 0179 E672 250 JNC REP 017B 23F8 251 MOV A,#0F8H 017D 34E2 252 CALL FRAME ;POST AMBLE 017F 09 253 IN A,PI ;APAGA FSK 018099FE 254 ANL P1,#0FEH 0182 39 255 OUTL P1,A 0183 0420 256 JMP ONHOOK 0185 BB00 257 BUSREQ: MOV BE,#TT1 ;TT10-1 WILL PEE- 018709 258 IN A,PI ;TURN MY FSK OFF 018853FE 259 ANL A,#OFEH 018A 39 260 OUTL PI,A 018B 34AB 261 CALL DELAY ;VENT ALL USERS AT 018D 08 262 IN A,PO ;THE .SAME TIME 018E 5303 263 ANL A,#03 ;IF I REC FSK M/S 0190 C685 264 JZ BUSEEQ ;H=EEADY NO M/S 0192 09 265 IN A,PI 01934301 266 ORL A,#01H 019502 267 OUTL BUS,A 0196 587 268 OEL A,#87H • GRAB BUS MONOPULS 0198 39 269 OUTL PI,A • OUT MARK 0199 BBOA 270 MOV R3,#TTM • OAH-10H 019B 34AB 271 CALL DELAY ■ H-XMIT 019D 08 272 IN A,P0 019E 4307 273 OEL A,#07H • SEND SPACE 01AO 02 ' 274 OUTL BUS,A 01A1 BBOA 275 MOV R3,#0AH ■ WAIT TO SEE IF AN 01A3 34AB 276 CALL DELAY • H SHOWS UP 01A509 277 IN A,PI • CHK COLLITION H-O 01A65302 278 ANL A,#02H • NO M,S AT SAME T. 01A8 C685 279 JZ BUSREQ ?IDSEND TURN FSK O 01AA 83 280 RET 01AB BC04 281 DELAY: MOV R4,#04 ;DEL SUBLOOP 01AD FC 282 MOV A,R4 01AE 07 283 DELI: DEC A 01AF E6AE 284 JNC DELI 01B1 FB 285 MOV A,R3 01B2 CB 286 DEC R3 01B307 287 DEC A 01B4 E6AB 288 JNC DELAY 01B683 289 RET 01B723F0 290 IDSEND: MOV A,#0F0H ;SEND A COMPL FRAM 01B934E2 291 CALL FRAME 01BB FD 292 MOV A,R5 01BC 34E2 293 CALL FRAME 01BE 540C 294 CALL NUMBER ;MY # 010034DB 295 CALL DE-MORA 01C2 5424 296 CALL CALNUM 01C434DB 297 CALL DEMORA 01C6 FF 298 MOV A,R7 01C734E2 299 CALL FRAME C1C934DB 300 CALL DEMORA 01CB 23F8 301 MOV A,#0F8H ;POST OICD 34E2 302 CALL FRAME BSTITUTE SHEET OICF 09 303 IN A,PI ;TURN MY FSK OFF 01D099FE ' 304 ANL P1,#0FEH 01D239 305 OUTL PI,A 01D383 306 RET 01D424D6 307 DELAYT: JMP DELT1 01D624D8 308 DELT1: JMP DELT2 01D824D1 309 DELT2: JMP EELT3 01DA 83 310 DELT3: RET 01DB BB02 311 DEMORA: MOV EE,#02H 01DD 34AB 312 CALL DELAY 01DF 00 313 NOP 01E000 314 NOP 01E183 315 RET 01E2 BC08 316 FRAME: MOV R4,#08 .SEND 8 BIT FROM A 01E4 AA 317 MOV R2,A ;SAVE A(ID) IN 42 01E508 318 FRAMEl: IN A,PO ;SEND MARK 01E64380 319 ORL A,#80H 01E802 320 OUTL BUS,A 01E9 FA 321 MOV A,R2 01EA F7 322 RLC A ;RETUEN A VAL 01EB E6F9 323 JNC TSPACE 01ED AA 324 MOV R2,A 01EE 24F0 325 JMP D 01F024F2 326 D: JMP DD 01F200 327 DD: NOP 01F3 24F5 328 JMP DELAYS 01F534D4 329 DELAYS: CALL DELAYT 01F724FC 330 JMP ENVIAR 01F9 AA 331 TSPACE: MOV R2.A 01FA 5402 332 CALL SPACE 01FC 5402 333 ENVIAR: CALL SPACE 01FE CC 334 DEC R4 01FF 96E5 335 JNZ FRAMEl 020183 336 RET 020208 337 SPACE: IN A,P0 0203 537F 338 ANL A,#7FH :OFF 020502 339 OUTL BUS,A 0206 34D4 340 CALL DELA-.T SUBSTITUTE SHEET 020883 341 BET 020900 342 NOP 020A 00 343 NOP 020B 00 • * 344 NOP 020C BE3F 345 NUMBER: MOV R6,#3FH :MY # ADR 11-17 020E FE 346 NUMB: MOV A,R6 020F A3 347 MOVP A, A 021034E2 348 CALL FRAME 0212 IE 349 INC R6 0213 23BB 350 MOV A,#187D ;DIG COUNT COMPLEM 026E 351 ADD A,R6 ;EF+17=0 17 LAST # 0216 960E 352 JNZ NUMB ;ADRS 021883 353 RET 02199A00 354 EESETL: ANL P2,#00 ;RESET PLL,IDD, EC 021B 08 355 IN A,PO 021C 539F 356 ANL A,#9FH 021E 02 357 OUTL BUS,A 021F Fl 358 MOV . A, Rl 0220 533F 359 ANL A,#3FH 0222 Al 360 MOV R1,A 0223 83 361 RET 0224 B818 362 CAINUM: MOV RO,#18H ;24 STR ADRS OF CA- 0226 F8 363 CAIT: MOV A,RO ;LLED # 0227 PO 364 MOV A, RO 0228 34E2 365 CALL FRAME 022A 34AB 366 CALL DELAY 022C 18 367 INC PO 022D 23E1 368 MOV A,#0E1H 022F 68 369 ADD A,RO .COUNT E1H+31D=0 02309626 370 JNZ CAIN 023283 371 RET 0233 BCFF 372 LDELAY: MOV R4,#0FFH ;200K STATES .5SEC 0235 FC 373 MOV A,R4 023607 374 LDEL1: DEC A 0237 E636 375 JNC LDEL1 ;[ 3 0239 FB 376 MOV A,R3 023A CB 377 DEC R3 023B 07 378 DEC A SUBSTITUTE SHEET 023C E633 379 JNC LDELAY 023E 83 380 RET 023F 08030- 381 DB 8,3,5,1,2,3,4 501 ., 0243 020304 024600 382 NOP 0247 7408 383 INTE: CALL BYTE ;READ SYNC, R2-REC B 0249 FA 384 MOV A,R2 TINT IS GEN AT LEAS 024A 17 385 INC A ;T 6 STATES BEFORE 024B C64F 386 JZ TEMP10 024D 6485 387 JMP SALIDA ;READ 024F 7408 388 TEMP10: CALL BYTE 0251 FA 389 MOV A,R2 0252 17 390 INC A 0253 17 391 INC A 0254 C6C4 392 JZ IDASK 0256 17 393 INC A 0257 C666 394 JZ IDS 025917 395 INC A 025A C695 396 JZ IDLF 025C 17 397 INC A 025D C67E 398 JZ IDR 025F 17 399 INC A 0260 C6AD 400 JZ IDD 0262 17 401 INC A 0263 C6D9 402 JZ REPLY 026583 403 RET 0266 744A 404 IDS: CALL CHECK :RO-MmSAJERO 026818 405 INC RO ;MY # 0269 F66D 406 JC IDS2 ;READ RO FOR FF 026B 44EE 407 JMP SETBIT 026D 7408 408 IDS2: CALL BYTE ;LEGR CH EN R7 026D FA 409 MOV A,R2 0270 AF 410 MOV R7,A 0271 743F 411 CALL POST 0273 18 412 INC RO 0274 F678 413 JC SFLA 027683 414 RET 0277 Fl 415 MOV A, Rl 02784304 416 SFIA: ORL ' A,#04H :SET IDS FLA 027A Al 417 MOV R1,A 027B 7428 418 CALL ONDATA 027D 83 419 RET 027E 744A 420 IDR: CALL CHECK 028018 421 INC EO 0281 F684 422 JC IDR2 0283 83 423 RET 02847408 424 IDR2: CALL BYTE 0286 FA 425 MOV A,R2 0287 AF 426 MOV R7,A 0288 743F 427 CALL POST 028A 18 428 INC EO 028B F68E 429 JC RFLA 028D 83 430 RET 028E Fl 431 RFLA: MOV A, Rl 028F 4380 432 ORL A,#80H 0291 Al 433 MOV R1,A 0292 7428 434 CALL ONDATA 029483 435 RET 0295 744A 436 IDLF: CALL CHECK 0297 18 437 INC RO 0298 F69C 438 JC IDL2 029A 44FA 439 JMP RESBIT 029C 7408 440 IDL2: CALL BYTE 029E FA 441 MOV A,R2 029E AF 442 MOV R7,A 02AO 743F 443 CALL POST 02A218 444 INC RO 02A3 F6A6 445 JC LF A 02A583 446 EET 02A6 Fl 447 LFLA: MOV A, Rl 02A74301 448 OEL A,#01 02A9 Al 449 MOV E1,A 02AA 746D 450 CALL OFDATA 02AC 83 451 RET 02AD 744A 452 IDD: CALL CHECK SUBSTITUTE SHEET AF 18 453 INC RO B0 F6B3 454 FC IDD2 B283 455 EET B3 74J38 456 IDD2 : CALL BYTE B5 FA 457 MOV A,R2 B6 AF 458 MOV R7,A B7743F 459 CALL POST B918 460 INC EO BA F6BD 461 JC DFLA BC 83 462 EET BD Fl 463 DFLA: MOV A, El BE 4340 464 OEL A,#40H C0 Al 465 MOV R1,A C17428 466 CALL ONDATA C383 467 EET C4744A 468 IDASK: CALL CHECK C618 469 INC RO C7 F6CA 470 JC IDASK2 C983 471 EET CA 7408 472 IDASK2 ; CALL BYTE CC FA 473 MOV A,R2 CD AF 474 MOV R7,A CE 743F 475 CALL POST DO 18 476 INC RO D1 F6D4 477 JC ASFLA D383 478 RET D4 Fl 479 ASFLA: MOV A, Rl D54310 480 OEL A,#10H D7 Al 481 MOV R1,A D883 482 RET D9 Fl 483 EEPLY: MOV A, Rl ■ RESET ASK FLA DA 53EF 484 ANL A,#OEFH ■ I(3SIORE REC 111 DC Al 485 MOV R1,A • WRONG SYNC 111 DD 5310 486 ANL A,#10H , • CHK RECREP DF C6ED 487 JZ SALID5 E1 BC60 488 MOV R4,#96 E3 B820 489 MOV RD,#32 ;RECREP OK FLA E5 7408 490 C0NT9: CALL BYTE ITUTE SHEET 02E7 FA 491 MOV A,R2 02E8 AO 492 MOV RO,A rUPDATE 02E9 18 493 INC RO 02EA IC ' • * 494 INC R4 02EB E6E5 495 JNC CONT9 02ED 83 496 SALID5: RET 02EE 7408 497 SETBIT: CALL BYTE :SET CH BIT AFT IDS 02F0 FA 498 MOV A,R2 02F1 AF 499 MOV R7,A 02F2743F 500 CALL POST 02F418 501 INC RO 02F5 F6F9 502 JC SETC 02F7 7428 503 CALL ONDATA 02F983 504 SETC: RET 02FA 7408 505 RESBIT: CALL BYTE 02FC FA 506 MOV A,R2 02FD AF 507 MOV R7,A 02FE 743F 508 CALL POST 0300 18 509 INC RO 0301 F605 510 JC RESC 0303 746D 511 CALL OFDATA 0305 83 512 RESC: RET 0306 00 513 NOP 0307 00 514 NOP 0308 BEF8 515 BYTE: MOV R6,#0F. ; EER BYTE, COUNT 8 030A BAOO 516 MOV R2,#00I 030C 08 517 WAIT: IN A,PO ;WAIT FOR MARK 030D 5302 518 ANL A,#02 030F C60C 519 JZ WAIT 0311 34D4 520 CALL DELAYT 0313 34D4 521 CALL DELAYT 0315 08 522 IN A,PO ;LEER 0316 5302 523 ANL A,#02 0318 C61F 524 JZ C0NT5 031A FA 525 MOV A,R2 031B 17 526 INC A 031C FA 527 MOV A,R2 031D 00 528 NOP su B sriruTz SH 031E 00 529 NOP 031F FA 530 CONT5: MOV A,R2 0320 F7 531 RLC A 0321 AA • * 532 MOV R2,A ;R2 TIENE EL BY REC 0322 IE 533 INC R6 0323 C627 534 JZ WAIT8 0325 640C 535 JMP WAIT 0327 83 536 WAIT8: .EET 0328 FF 537 ONDATA: MOV A,R7 ;SET ON CH ON USE B 0329 BEOO 538 MOV R6,#00 032B 77 539 RR A ;DIVIDE BY 8 032C 77 540 ER A 032D 77 541 RR A 032E 0320 542 ADD A,#20H 0330 AS 543 MOV RO,A ;BYTE DEL STATUS 0331 FF 544 MOV A,R7 03325307 545 ANL A,#07 033437 546 CPL A 0335 AE 547 MOV R6,A 03362301 548 MOV A,#01 0338 E7 549 ON2: RL A 0339 IE 550 INC R6 033A E638 551 JNC 0N2 033C 40 552 OEL A, RO ;OFDATA 033D AO 553 MOV R0,A 033E 83 554 RET 033F 7408 555 POST: CALL BYTE 0341 FA 556 MOV A,R2 03420308 557 ADD A,#08 ;COMP F8= 0344 C647 558 JZ BIEN 034683 559 RET 0347 B8FF 560 BIEN: MOV R0,#0FFH 0349 83 561 RET 034A BBOC 562 CHECK: MOV R3,#TT400 034C 34AB 563 CALL DELAY 034E B886 564 MOV RO,#86H 03507408 565 MINUM: CALL BYTE 0352 F8 566 MOV A,R0 03530374 567 ADD A,#TTX 0355 C664 568 JZ EXIT 0357 F8 569 MOV A,ED 035818 • * 570 INC RO 0359 A3 571 MOVP A, A 035A 37 572 CPL A 035B 6A 573 ADD A,R2 035C 9650 574 JNZ MINUM 035E Fl 575 MOV A, Rl 035F 4320 576 ORL A,#20H ;SET INT FLA INDICA- 0361 Al 577 MOV R1,A ; TES NOT MY # 03626450 578 JMP MINUM 0364 F9 579 EXIT: MOV A,R1 0365 5320 580 ANL A,#20H 0367 C66A 581 JZ CK 036983 582 RET 036A B8FF 583 OK: MOV EO,OFFH 036C 83 584 RET 036D FF 585 OFDATA: MOV A,R7 036E BEOO 586 MOV R6,#00 0370 77 587 RR A 0371 77 588 RR A 0372 77 589 RR A 0373 77 590 ADD A,#32 0375 A8 591 MOV R0,A ;BYTE DEL STATUS 0376 FF 592 MOV A,R7 0377 5307 593 ANL A,#07 0379 37 594 CPL A 037A AE 595 MOV R6,A 037B 2301 596 MOV A,#01 037D E7 597 OF2 : RL A 037E IE 598 INC ' R6 037F E67D 599 JNC OF2 0381 37 600 CPL A 0382 07 601 DEC A ;IF IT IS 2'S COMP. 0383 50 602 ANL A, RO 0384 AO 603 MOV EO,A 038583 604 SALIDA: EET SUBSTITUTE SHEET 03860803- 605 DB 8, 3, 5, 1, 2, 3,4 0501 038A 020304 038D Cft., 606 DΞBUG1 : IN A,P2 038E 5303 607 ANL A,#03 0390 AB 608 MOV R3,A 0391 FC 609 MOV A,R4 0392 E7 610 RL A 0393 E7 611 EL A 03944C 612 ORL A,4R 0395 3A 613 OUTL P2,A 039683 614 RET 0397 Fl 615 DEBUG: MOV A, Rl 039853D4 616 ANL A,#0D4H 039A AB 617 MOV R3,A 039B 5301 618 ANL A,#01 039D E7 619 EL A 039E E7 620 RL A 039F E7 621 RL A 03AO E7 622 RL A 03A14B 623 ORL A,R3 03A2 AB 624 MOV R3,A 03A3 Fl 625 MOV A, Rl 03A45302 626 ANL A,#02 03A647 627 SWAP A 03A74B 628 ORL A,R3 03A83A 629 OUTL P2,A 03A983 630 RET 631 END 632 633 ASSEMBLY COMPLETE, 0 ERRORS FOUND SUBSTITUTE SHEET ASFLA '. . . . C ADDR 02D4H ASK C ADDR OOFFH ASKFLA C ADDR 0150H BEGIN C ADDR 0005H BIEN C ADDR 0347H BUSREO C ADDR 0185H BYTE C ADDR 0308H BZTONE C ADDR 00A4H CALING C ADDR 006DH CALN C ADDR 0226H CALNUM C ADDR 0224H CHECK C ADDR 034AH CONT C ADDR 0080H CONT5 . . ' C ADDR031FH C0NT9 C ADDR 02E5H CORTA C ADDR 00E7H D C ADDR 01FOH DD . • C ADDR 01F2H DEBUG C ADDR 0397H DEBUG1 C ADDR 038DH DELI C ADDR OlAFH DELAY C ADDR 01ABH DELAY8 C ADDR 01F5H DELAYT C ADDR 01D4H DELT1. ' C ADDR 01D6H DELT2 C ADDR 01D8H DELT3 C ADDR 01DAH DEMORA C ADDR 01DBH DESC1 C ADDR O10FH DFLA C ADDR 02BDH ENGAN C ADDR 013EH ENVIAR . C ADDR OlFCH EXIT C ADDR 0364H FRAME C ADDR 01E2H FRAMEl C ADDR 01E5H FRAME3 C ADDR 007AH H20 C .ADDR 0046H H40 C ADDR 0036H SUBSTITUT H40C C ADDR 003AH IDASK C ADDR 02C4H IDASK2 C ADDR 02CAH IDD. . . , C ADDR 02ADH IDD2 C ADDR 02B3H IDL2 C ADDR 029CH IDLF C ADDR 0295H IDLXMIT C ADDR 00B5H NOT USED IDR C ADDR 027EH IDR2 C ADDR 0284H IDS C ADDR 0266H IDS2 C ADDR 026DH IDSEND C ADDR 01B7H INTE . . C ADDR 0247H L60 C ADDR 0247H L60C C ADDR 0055H LDEL1. C ADDR 0236H LDELAY C ADDR 0233H LFLA C ADDR 02A6H LOADD C ADDR 0134H MAXL C ADDR 005FH MINUM. C ADDR 0350H NUMB C ADDR 020EH NUMBER . C ADDR 020CH OF2 C ADDR 037DH OFDATA C ADDR 036DH OK . . C ADDR 036AH ON C ADDR 002BH ON2 C ADDR 0333H ONDATA C ADDR 0328H ONHOOK C ADDR 0020H PLL C ADDR 008BH NOT USED POST C ADDR 033FH RECFLA C ADDR OOAOH NOT USED RECIDS C ADDR 0OF8H RECTIM C ADDR OOBFH REP C ADDR 0172H REPLY C ADDR 02D9H RESBIT C ADDR 02FAH RESC C ADDR 0305H RESETL C ADDR 0219H RESIDS. C ADDR 014CH RFLA C ADDR 028EH SALID5 C ADDR 02EDH SALIDA C ADDR 0385H SETBIT C ADDR 02EEH SETC C ADDR 02F9H SFLA C ADDR 0278H SPACE C ADDR 0202H TEMPI C ADDR 0162H TEMP10 . C ADDR 024FH TEMP2 C ADDR 0157H TSPACE C ADDR 01F9H TT1 NUMB OOOOH TT10 NUMB OOOIH TT40 NUMB OOOCH TT50 NUMB 0062H- TT51 NUMB 0071H TT52 NUMB 001CH TT8 NUMB OOFFH TT9 NUMB OOFFH TTM NUMB OOOAH TTX NUMB 0074H WAIT C ADDR 030CH WAIT8 C ADDR 0327H WHAT I CLAIM IS: l.A communications network which comprises: means to establish a data signaling channel in a coaxial cable; means to establish a plurality of voice channels sepa¬ rate from the data signaling channel in said cable; means to send a signal from a first source through the data signaling channel to a second source to determine if the second source is able to accept a signal transmission from the first source; SUBSTITUTE SHEET

Claims: eans to select a voice channel to transmit a signal from the first source to the..second source if the second source is available to receive the transmitted signal; means to transmit a signal from the second source to the first source on a separate voice channel; and means to signal that said voice channels are open for communication between said sources . 2. A method of telephonic communication which in¬ cludes; establishing a data signaling channel in a coaxial cable; defining a plurality of voice channels separate from the data signaling channel in said cable; ' sending a signal from a first source through the data signaling cable to a second source to determine if the second source is able to accept a signal transmission from the first source; selecting a voice channel to transmit a signal from the first source to the second source if the second source is available to receive the transmitted .signal; transmitting a signal from the second source to the first source on a separate voice channel; and signaling that said voice channels are open for commu¬ nication between said sources. SUBSTITUTE SHEET

Inventors: SOTO JOSE MANUEL, SOTO, JOSE, MANUEL
Applicants: SOTO JOSE MANUEL, SOTO, JOSE, MANUEL
Application year: 1986
Main classification: H04J1
IPC codes: H04M9