Abstract:
According to a method and apparatus disclosed herein, an electronic register advantageously logs raw sensor data without converting the raw sensor data into physical-domain measurements, and without need for being configured to understand or process such data, or account or compensate for any sensor installation particulars. Instead, the electronic register advantageously stores conversion data in association with each sensor interface circuit being used to collect raw sensor data from a corresponding external sensor, and it provides the conversion data to an external device, in association with read-out of the raw sensor data logged by the electronic unit. The conversion data provides the mathematical expression, along with any compensation or adjustment values needed, to convert the raw sensor data into corresponding physical-domain measurements.

Description:
TECHNICAL FIELD 
     The present invention relates to electronic registers, and particularly relates to an electronic register that collects and provides sensor data. 
     BACKGROUND 
     “Electronic registers” find wide application across a broad range of industries, including the utility industries, where electronic registers provide critical metering capabilities for gas, electric, water, or other consumables provided on a metered basis. Electronic registers provide a ready mechanism for logging consumption data and, more generally, various types of sensor data, such as fluid level measurements, etc. 
     With their flexibility and wide usage, however, comes a number of challenges. For example, the designers, manufacturers, and distributors of electronic registers have a keen interest in reducing production costs, maintenance, and support issues, and simplifying the models that need to be stocked, serviced, etc. Customers, on the other hand, require electronic registers that are, in at least some respects, fine-tuned to their particular applications or installations. Difficulties, therefore, arise when attempting to field a base register design that accommodates a wide range of applications, while offering needed features and particularized operation suiting specific applications. 
     To appreciate some of these difficulties, consider the example components of a typical electronic register. In an exemplary but non-limiting case, an electronic register includes processing circuitry, communication circuitry, and sensor interface circuitry. However, the processing details and, in particular, the processing and logging of the sensor data, depends on the type of sensors and sensor data involved. The various aspects of data handling, such as resolution, scaling, etc., must be preprogrammed or otherwise provisioned in the electronic register before field deployment, which complicates production, distribution, inventory management, installation management, etc. 
     SUMMARY 
     According to a method and apparatus disclosed herein, an electronic register advantageously logs raw sensor data without converting the raw sensor data into physical-domain measurements, and without the need for being configured to understand or process such data, or account or compensate for any sensor installation particulars. Instead, the electronic register advantageously stores conversion data in association with each sensor interface circuit being used to collect raw sensor data from a corresponding external sensor, and it provides the conversion data to an external device, in association with the read-out of the raw sensor data logged by the electronic unit. The conversion data provides the mathematical expression, along with any compensation or adjustment values needed, to convert the raw sensor data into corresponding physical-domain measurements. 
     In an example method, the electronic register receives conversion data from a first external device, via communication interface circuitry of the electronic register, for a sensor interface circuit of the electronic register. The conversion data comprises information for converting raw sensor data obtained from an external sensor coupled to the sensor interface circuit into corresponding physical-domain measurements, and the electronic register stores the conversion data in the electronic register, in logical association with the sensor interface circuit. 
     Further, according to the method, the electronic register obtains the raw sensor data from the external sensor, via the sensor interface circuit, and logs the raw sensor data in the electronic register, in logical association with the stored conversion data, and without converting the logged raw sensor data into the corresponding physical-domain measurements. Still further, the electronic register outputs the stored conversion data and the logged raw sensor data logically associated with the stored conversion data, to the same or another external device, via communication interface circuitry of the electronic register. The electronic register performs the outputting operation responsive to a trigger, e.g., detection of the external device, or receipt of a request for such information, etc. 
     In a related example, an electronic register comprises communication interface circuitry configured for communicating with one or more external devices, a sensor interface circuit configured to interface with an external sensor, and processing circuitry including or operatively associated with the communication interface circuitry, the sensor interface circuit, and storage. The processing circuitry is configured to receive conversion data from a first external device, for the sensor interface circuit, the conversion data comprising information for converting raw sensor data obtained from the external sensor into corresponding physical-domain measurements. 
     The processing circuitry is further configured to store the conversion data in the storage, in logical association with the sensor interface circuit, obtain the raw sensor data from the external sensor, via the sensor interface circuit, and log the raw sensor data in the storage, in logical association with the stored conversion data, and without converting the logged raw sensor data into the corresponding physical-domain measurements. Further, in response to a trigger, the processing circuitry is configured to output the stored conversion data and the logged raw sensor data logically associated with the stored conversion data, to the first external device, or to a second external device. 
     In yet another example, an electronic register implements a method that includes receiving conversion data for each of two or more sensor interface circuits of the electronic register, wherein the conversion data received for each sensor interface circuit comprises information for converting raw sensor data obtained from the sensor interface circuit into corresponding physical-domain measurements. The method includes storing the conversion data received for each sensor interface circuit in logical association with the sensor interface circuit, logging the raw sensor data obtained from each sensor interface circuit in logical association with the conversion data received and stored for the sensor interface circuit, and without converting the raw sensor data into the corresponding physical-domain measurements. Further, the method includes outputting the logged raw sensor data for any one of the sensor interface circuits to an external device, along with the conversion data received and stored for the sensor interface circuit, thereby enabling the external device to convert the logged raw sensor data into the corresponding physical-domain measurements. 
     Of course, the present invention is not limited to the above features and advantages. Those of ordinary skill in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of one embodiment of an electronic register configured to interface with one or more external sensors and to log raw sensor data obtained therefrom. 
         FIG. 2  is a diagram of one embodiment of the logical associations contemplated herein for the storage of logged raw sensor data and corresponding conversion data. 
         FIG. 3  is a logic flow diagram of one embodiment of a method of operation at an electronic register. 
         FIG. 4  is a logic flow diagram of another embodiment of a method of operation at an electronic register. 
         FIG. 5  is a schematic diagram of one embodiment of a sensor interface circuit configured for obtaining raw sensor data from an external sensor. 
     
    
    
     DETAILED DESCRIPTION 
     By way of non-limiting example,  FIG. 1  illustrates an embodiment of an electronic register  12 . According to the example, the electronic register  12  includes communication interface circuitry  14 , which in turn includes a radio frequency (RF) transceiver circuit  16 , and a “local” wired or wireless communication interface circuit  18 . Further included are one or more sensor interface circuits  20 , shown by way of example as sensor interface circuits  20 - 1  through  20 -N, processing circuitry  22 , storage  24 , and a power supply  26 . 
     Each sensor interface circuit  20  is configured to interface with an external sensor  30 . e.g., the sensor interface circuit  20 - 1  interfaces with an external sensor  30 - 1 , and the sensor interface circuit  20 - 2  interfaces with an external sensor  30 - 2 . The number “ 20 ” is used without suffixing to refer to single sensor interface circuits, and to refer to multiple sensor interface circuits. Suffixing appears only where needed for clarity and use of the reference number  20  in this generalized fashion does not mean that each sensor interface circuit  20  is identical to the next one. The reference number “ 30 ” is used the same way, and such usage does not mean that each external sensor  30  is identical to the next one. 
     In some embodiments, the electronic register  12  does include two or more sensor circuits  20  that are “like” sensor circuits, i.e., of the same type, design, and implementation. For example, the at least two like sensor interface circuits  20  comprise two or more analog current loop interfaces or two or more analog voltage interfaces having like nominal current or voltage ranges. In the same embodiment, or in other embodiments, however, at least two of the sensor interface circuits  20  are different in type, design, and implementation. One type of sensor interface circuit  20  comprises a digital counter or pulse input, another type of sensor interface circuit  20  comprises a current signal interface, and yet another type of sensor interface circuit  20  comprises a voltage signal interface. 
     The electronic register  12  provides advantageous mechanisms for interfacing with individual sensors  30 , with respect to their particular sensor types, their particular operational characteristics, and their particular installation details. These mechanisms may be exercised or accessed. e.g., through the communication interface circuit  18  and/or through the RF transceiver circuit  16 , if present and configured for such use. 
     In an example implementation, the communication interface circuit  18  is configured for communicating with one or more external devices  32  that are used to read sensor data and associated information from the electronic register  12 . In at least one embodiment, the communication interface  18  allows an external device  32  to configure the electronic register  12  with respect to individual ones of the sensor interface circuits  30 . Two external devices  32 - 1  and  32 - 2  are shown by way of example, e.g., the device  32 - 1  may be operative as a “configurator” for setting up the electronic register  12  with respect to one or more external sensors  30 , while the device  32 - 2  may be operative as a “reader” or “interrogator” for reading out logged sensor data and other information from the electronic register  12 . Of course, the same device  32  may provide both capabilities, based on user authorization, etc. In an example case, a laptop computer is configured to operate as the external device  32 - 1  and/or  32 - 2 , but proprietary or dedicated devices  32  may also be used. 
     Other means of accessing or communicating with the electronic register are available in embodiments that include the RF transceiver circuit  16 . That circuitry comprises, for example, a cellular radio modem or other wide-area radio interface that is configured to communicatively couple the electronic register  12  to an Advanced Metering Infrastructure (AMI), such as represented by the depicted radio network  34  and the associated radio network node  36 . 
     Other embodiments of the electronic register  12  may omit the RF transceiver circuit  16 , in favor of relying on the local communication interface  18  for the collection of logged data, etc., by one or more external devices  32 . Non-limiting examples of the local communication interface circuit  18  include Near Field Communication (NFC) circuitry, a Wi-Fi interface, a Bluetooth interface, an Ethernet interface, or an RS-232 or other wired serial interface. In general, the local communication interface circuit  18  is configured for bi-directional communication between the electronic register  12  and one or more external device(s)  32 . 
     With the above in mind, in at least one embodiment, the electronic register  12  comprises communication interface circuitry  14  configured for communicating with one or more external devices  32 , a sensor interface circuit  20  configured to interface with an external sensor  30 , and processing circuitry  22  including or operatively associated with the communication interface circuitry  14 , the sensor interface circuit  20 , and storage  24 . The processing circuitry  22  is configured to receive conversion data from a first external device  32 - 1 , for the sensor interface circuit  20 . The conversion data comprises information for converting raw sensor data obtained from the external sensor  30  into corresponding physical-domain measurements, and the processing circuitry  22  is configured to store the conversion data in the storage  24 , in logical association with the sensor interface circuit  20 . 
     The processing circuitry  22  is further configured to obtain the raw sensor data from the external sensor  30 , via the sensor interface circuit  20 , and log the raw sensor data in the storage  24 , in logical association with the stored conversion data, and without converting the logged raw sensor data into the corresponding physical-domain measurements. That approach enables the processing circuitry  22  to log data from an arbitrary sensor chosen by the user, but unknown to the manufacturer of the electronic register  12  a priori. No firmware modification is required to support a different type of sensor, yet multiple interrogation devices can use the conversion data and display physical-domain measurement values to the user. 
     The processing circuitry  22  also increases its efficiency and avoids complexity by logging the raw sensor data, rather than “converting” the raw sensor data into units of measurement associated with the physical parameter being measured by the involved external sensor  30 . The capability of making such conversions is, however, advantageously preserved by maintaining the logged raw sensor data in logical association with the stored conversion data needed to convert the logged raw sensor data into corresponding physical-domain measurement values. 
     In particular, the processing circuitry  22  is configured to, in response to a trigger, output the stored conversion data and the logged raw sensor data logically associated with the stored conversion data, to the first external device  32 - 1 , or to a second external device  32 - 2 . The trigger may be external—such as a reading event—or may be internal, such as the expiration of a timer internal to the electronic register  12 . The processing circuitry  22  in at least some embodiments is configured to output the stored conversion data and the associated logged raw sensor data to a metering network—i.e., the AMI infrastructure—via the RF transceiver circuit  16 . 
     As an example, the “trigger” in question is the detection by the electronic register  12  the presence of an external device  32 . Such detection may be more nuanced. For example, “detection” in one or more embodiments comprises detecting the presence of the external device  32 , and determining that the external device  32  is authorized to receive logged raw sensor data, etc., from the electronic register  12 . Authorization may be determined based on simple protocol handshaking, or may be more involved, e.g., password or other credential verification, or key-based authentication. In another example, the “trigger” in question is the receipt of request or command from an external device  32 . 
     In one or more embodiments, the processing circuitry  22  is configured to obtain the raw sensor data from any given external sensor  30  by reading a sensor signal output from the external sensor  30  and normalizing the readings according to a defined numeric representation. Here, it will be understood that the processing circuitry  22  uses the corresponding sensor interface circuit  20  to “read” the sensor signal output from the external sensor  30 . In at least one such embodiment, the processing circuitry  22  is configured to normalize the readings according to the defined numeric representation. For example, the processing circuitry  22  normalizes the readings by formatting them according to a defined fixed-point or floating-point data type used by the electronic register  12 . The data normalization allows the electronic register to handle readings from disparate sensor types and/or configurations in a uniform manner, and it simplifies logging, memory management, etc. In turn, these simplifications correspond to simplifications in the design, programming, and operation of the electronic register  12 . 
     As an example of the advantages flowing from the normalization of raw sensor data, the processing circuitry  22  in one or more embodiments is configured to obtain the raw sensor data from a given external sensor  30  as digital readings obtained from the sensor interface circuit  20  associated with the given external sensor  30 . In this example, the sensor interface circuit  20  is configured to digitize an analog sensor signal output by the given external sensor  30 . Additionally, or alternatively, the electronic register  12  includes a sensor interface circuit  20  that is configured to receive an analog or digital signal from an external sensor  30  that is indicative of count values, and the processing circuitry  22  is configured to log the indicated count values in a normalized form. 
     In another illustrative example, the electronic register  12  includes at least two sensor interface circuits  20 . e.g., a first sensor interface circuit  20 - 1  and a second sensor interface circuit  20 - 2 . The processing circuitry  22  is configured to receive and store respective conversion data for each of the sensor interface circuits  20 , log the raw sensor data obtained for each sensor interface circuit  20  in logical association with the respective stored conversion data, and, when outputting the logged raw sensor data for any given one of the sensor interface circuits  20 , to output the respective stored conversion data. 
     In more detail, the processing circuitry  22  is configured to store conversion data for a sensor interface circuit  20 - 1 /external sensor  30 - 1 , log raw sensor data obtained from the sensor interface circuit  20 - 1  in logical association with the corresponding conversion data, and output that corresponding conversion data for the logged raw sensor data. The same operations are performed with respect to a sensor interface circuit  20 - 2 /external sensor  30 - 2 . Consequently, regardless of whether the two external sensors  30 - 1  and  30 - 2  are nominally the same, the particulars of each sensor installation can be accounted for without modifying the basis operation of the electronic register  12 , simply by loading appropriately configured conversion data into the electronic register  12 , for each external sensor  30 . 
     In this regard, the conversion data stored by the processing circuitry  22  in the storage  24  for any particular sensor interface circuit  20  and its corresponding external sensor  30  comprises, for example, the calculation or formula used for converting the corresponding logged raw sensor data into physical-domain measurements. For example, an external sensor  30  outputs an analog voltage or current signal corresponding to sensed gas pressure in PSI, the associated sensor interface circuit  20  digitizes the sensor signal into corresponding analog-to-digital converter (ADC) count values, e.g., values between 0 and 1023 for a ten-bit ADC. 
     These count values, which may be normalized, e.g., to a 32-bit format, correspond to a range of gas pressure and the conversion data would be, for example: 
                 P   measured     =         court   logged     1023     ×     P   max         ,         
where P max  is the top of the sensing pressure range, and count logged  is the raw ADC count value (in normalized form).
 
     However, it is contemplated herein that the conversion data in one or more embodiments provides for a much richer pairing of given external sensors  30  to the electronic register  12 , without adding any complication to the operation of the electronic register  12 . For example, the conversion data loaded into the electronic register  12  for a given external sensor  30  may include one or more calibration values, e.g., coefficients for scaling errors, sensor offsets, etc. The “intelligence” for parsing and applying the conversion data resides in the external devices  32  (and/or remote network nodes), rather than in the electronic register  12 . Moreover, the electronic register  12  need only reserve sufficient storage for holding the conversion data for each of its sensor interfaces  20 , e.g., 512 bytes, 1024 bytes, etc., to serve as a blank slate for loading whatever type of conversion data is needed or desired. 
     Such an approach obviates the need for preconfiguring the electronic register  12  for the particulars of any installation, as the only real requirement is that the electronic register  12  includes sensor interface circuits  20  that are compatible with the type(s) of external sensor(s)  30  deployed at a given installation. Moreover, the electronic register  12  from one location can be moved to another location and immediately be “tuned” or adapted to the particulars of the external sensors  30  at the new location, merely by loading the appropriate conversion data into the electronic register  12 . 
     As another advantage, it is contemplated herein that one or more embodiments of the electronic register  12  are configured to provide alarm functionality with respect to the external sensors  30 . e.g., to alarm on high or low signals, signal ranges, etc., corresponding to critical physical-domain measurement thresholds or ranges. Because the electronic register  12  foregoes any conversion of the logged raw sensor data into the physical domain, it advantageously ties its alarm functionality to an alarm threshold provided to it for any given sensor interface circuit  20 . The alarm threshold is expressed as a unit-less numeric value in a same numeric range as used for the logged raw sensor data obtained from the involved external sensor  30 . For example, the alarm threshold is expressed in normalized ADC counts. 
     The processing circuitry  22  is configured to receive such alarm thresholds from an external device  32  and/or through the radio network  34 , and to store the alarm thresholds in logical association with the respective sensor interface circuits. The processing circuitry  22  is further configured to output an alarm signal responsive to determining that the logged raw sensor data from a given external sensor  30  violates the alarm threshold loaded in the electronic register  12  for that sensor  30 . 
     Still further, in one or more embodiments, the processing circuitry  22  is configured to receive, store, and subsequently output reverse conversion data for any given sensor interface circuit  20 . The reverse conversion data comprises information for converting the involved physical domain measurements into corresponding raw sensor data values, thereby enabling an external device  32  to use the reverse conversion data to convert physical-domain alarm thresholds expressed in physical-domain measurement units into corresponding unit-less alarm thresholds for the electronic register  12 . In other words, an operator of the external device  32  sets an alarm threshold in the physical domain, e.g., sets a high or low gas pressure alarm in PSI, and the external device  32  calculates the corresponding raw sensor data values and returns those values to the electronic register  12  as alarm thresholds. 
     The outputting of alarm signals comprises, for example, outputting alarm signaling via the local communication interface  18  and/or via the RF transceiver circuit  16 , for network-based alarm reporting. 
     More generally, in at least one embodiment, the electronic register  12  is configured to output its stored conversion data and the logged raw sensor data logically associated with the stored conversion data, based on transmitting the stored conversion data and the logged raw sensor data to the radio network node  36 , as a first or second external device  32 . That is, in some embodiments, the external device  32  is a remote node or server communicatively coupled to the electronic register  12  via the radio network  34 . As noted, however, the first or second external device  32  may comprise a portable communication unit for reading or configuring the electronic register  12 . In such cases, the electronic register  12  is configured to communicate with the portable communication unit via a local wired or wireless connection. 
       FIG. 2  illustrates an example of the storage  24 , which in one or more embodiments provides volatile and non-volatile storage, e.g., working or data memory, along with program and data storage. While the storage  24  may comprise more than one type of storage—e.g., more than one type of memory or storage circuit—it shall be broadly understood as comprising a computer-readable medium, that includes storage for the aforementioned conversion data, the reverse conversion data, the alarm thresholds, and the logged raw sensor data. As suggested in the illustrated example, such storage is at least logically partitioned on a per-sensor interface circuit basis, so that such data is stored for each sensor interface circuit  20 . Of course, depending on the memory management implemented in the electronic register  12 , the storage  24  need not be pre-partitioned, and such partitioning may be purely logical and performed dynamically, or on an ad hoc basis, by the processing circuitry  22 . 
     The storage  24  in one or more embodiments also stores a computer program  38  comprising program instructions that, when executed by one or more processing circuits of the electronic register  12 , specially adapts such processing circuits to operate as the aforementioned processing circuitry  22 . For such operation, the storage  24  provides non-transitory storage for the computer program  38 , where “non-transitory” does not necessarily mean permanent or unchanging but does connote storage of at least some persistence, e.g., the program instructions are held in memory for execution. 
     As such, the storage  24  comprises, for example, SRAM, DRAM, or other working memory, along with FLASH, EEPROM, SSD, or other non-volatile storage circuitry, and the processing circuitry  22  in one or more embodiments comprises one or more microprocessor-based circuits, DSP-based circuits, ASIC- or FPGA-based circuits, or other digital processing circuitry. More broadly, the processing circuitry  22  comprises fixed circuitry, programmed circuitry, or a mix of fixed and programmed circuitry. Here, “fixed” circuitry denotes circuitry that is preconfigured to carry out particular operations or functions, while programmed circuitry takes on such configuration as a consequence of program instruction execution. 
       FIG. 3  illustrates a method  300  that may be implemented via the electronic register  12  of  FIG. 1 , or by another suitable register configuration. The method  300  includes receiving (Block  302 ) conversion data from an external device  32 , via communication interface circuitry  14  of the electronic register  12 , for a sensor interface circuit  20  of the electronic register  12 . The conversion data comprises information for converting raw sensor data obtained from an external sensor  30  coupled to the sensor interface circuit  20  into corresponding physical-domain measurements. 
     The method  300  further includes storing (Block  304 ) the conversion data in the electronic register  12 , in logical association with the sensor interface circuit  20 , obtaining (Block  306 ) the raw sensor data from the external sensor  30 , via the sensor interface circuit  20 , and logging (Block  308 ) the raw sensor data in the electronic register  12 , in logical association with the stored conversion data, and without converting the logged raw sensor data into the corresponding physical-domain measurements. Still further, the method  300  includes, responsive to a trigger, outputting (Block  310 ) the stored conversion data and the logged raw sensor data logically-associated with the stored conversion data, to the external device  32  (e.g., to any of devices  32 - 1  or  32 - 2 , or the radio network node  36 ), via the communication interface circuitry  14  of the electronic register  12 . 
       FIG. 4  illustrates a method  400 , which may be understood as a more detailed example or variation of the method  300 . The method  400  includes receiving (Block  402 ) conversion data for each of two or more sensor interface circuits  20  of the electronic register  12 , wherein the conversion data received for each sensor interface circuit  20  comprises information for converting raw sensor data obtained from the sensor interface circuit  20  into corresponding physical-domain measurements. 
     The method  400  further includes storing (Block  404 ) the conversion data received for each sensor interface circuit  20  in logical association with the sensor interface circuit  20 , and logging (Block  406 ) the raw sensor data obtained from each sensor interface circuit  20  in logical association with the conversion data received and stored for the sensor interface circuit  20 , and without converting the raw sensor data into the corresponding physical-domain measurements. Still further, the method  400  includes outputting (Block  408 ) the logged raw sensor data for any one of the sensor interface circuits  20  to an external device  32 , along with the conversion data received and stored for the sensor interface circuit  20 , thereby enabling the external device  32  to convert the logged raw sensor data into the corresponding physical-domain measurements. 
       FIG. 5  depicts an example sensor interface circuit  20 . By way of non-limiting example, the illustrated sensor interface circuit  20  is configured to receive a 4-20 mA current signal and includes terminals  40 - 1  and  40 - 2 , for connecting with the current-carrying wiring from an external sensor  30 , along with a resistor  42  (“R” in the diagram) used to develop a voltage signal proportional to the input current signal. An amplifier  44  (“AMP”) outputs a voltage-mode signal corresponding to the voltage developed across the resistor  42 , and an ADC  46  digitizes the output signal from the amplifier  44 . The processor circuitry  22  logs the ADC counts as the raw sensor data for the attached external sensor  30 . It will be appreciated that the amplifier  44  may be configured to provide buffering, filtering, gain, or other signal-conditioning, and that the sensor interface circuit  20  may include circuitry not shown, e.g., ESD protection circuitry, etc. 
     Notably, modifications and other embodiments of the disclosed invention(s) will come to mind to one skilled in the art having the benefit of the teachings presented in the preceding descriptions and the associated drawings. Therefore, it is to be understood that the invention(s) is/are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of this disclosure. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.