Slide 1: Transducer Electronic Data Sheets (TEDS) Lee H. Eccles Boeing Commercial Airplanes P. O. Box 3707, M/C 14-ME Seattle, WA 98124-2207 Lee.h.eccles@boeing.com 206-655-2824 1
Slide 2: Commercial Airplanes Airplane Validation Transducer Electronic Data Sheets What are they? A tool to enable true plug and play operation!  A method of supplying information to the user!  Why use them? To have plug and play operation!  To always be able to find the data sheet!  5/07/2002 Spring Sensors Expo 2002 2
Slide 3: Commercial Airplanes Airplane Validation Paper Data Sheets A paper data sheet contains: Information to be used to select the appropriate device for the task.  Information to be used to set up the system to be able to use the device.  There is no universally accepted format or required content. 5/07/2002 Spring Sensors Expo 2002 3
Slide 4: Commercial Airplanes Airplane Validation Electronic Data Sheets Electronic data sheets contains: Information to be used to select the appropriate device for the task.  Information to be used to set up the system to be able to use the device.  User information is free format. System information is in a fixed format. 5/07/2002 Spring Sensors Expo 2002 4
Slide 5: Commercial Airplanes Airplane Validation Information for the User The information should be text based.  Graphical information is desirable. There is different information required for each different device. No fixed format is practical.  Multiple languages must be supported.  5/07/2002 Spring Sensors Expo 2002 5
Slide 6: Commercial Airplanes Airplane Validation Information for the Users System Machine readable Many users will never try to read the information.  Others will.  The content must be defined in detail. It is this information that enables true plug and play operation. 5/07/2002 Spring Sensors Expo 2002 6
Slide 7: Commercial Airplanes Airplane Validation Three Standards, Four Interfaces Network Capable Application Processor (NCAP) with IEEE 1451.2 Interface Smart Transducer Interface Module (STIM) Transducer Independent Interface Transducer Independent Interface A/D or D/A Converter Signal Conditioner Transducer Physical Variable TEDS Interface Exposed by IEEE 1451.2 TEDS Network Capable Application Processor (NCAP) with IEEE p1451.3 Interface Interface Exposed by IEEE p1451.3 TEDS Transducer Bus Interface Module(s) Transducer(TBIM) Bus Interface Module (TBIM) Transducer Signal Transducer A/D or D/A Signal Bus Transducer A/D or D/A Conditioner Converter Bus Conditioner Transducer Interface Converter Interface TEDS Network Information provided by IEEE 1451.2 or IEEE p1451.3 TEDS Transducer Bus Interface Physical Variable Network Capable Application Processor (NCAP) with IEEE p1451.4 Interface Interface Exposed by IEEE p1451.4 TEDS A/D or D/A Converter Signal Conditioner IEEE p1451.4 Transducer Physical Variable Digital Interface TEDS 5/07/2002 Spring Sensors Expo 2002 7
Slide 8: Commercial Airplanes Airplane Validation Physical Variables What is measured or controlled?     Transducer type (i.e. pressure, temperature, flow, etc.) Range of measurement Unique features Etc. Information can be text based. The system does not need this information to operate. Spring Sensors Expo 2002 8 5/07/2002
Slide 9: Commercial Airplanes Airplane Validation Interface Information The standard defines the interface The TEDS provide the operational details Data format  Interface and data timing  Etc.  5/07/2002 Spring Sensors Expo 2002 9
Slide 10: Commercial Airplanes Airplane Validation TEDS Definition IEEE Std 1451.2-1997 provided the first standard to define TEDS. IEEE p1451.3 TEDS are patterned after IEEE Std 1451.2   Different interface Details are different Analog interface Different requirements Spring Sensors Expo 2002 10 IEEE p1451.4 TEDS are totally different   5/07/2002
Slide 11: Commercial Airplanes Airplane Validation Machine Readable TEDS IEEE Std 1451.2    IEEE p1451.3     Meta-TEDS Channel TEDS Calibration TEDS   Meta-TEDS Channel TEDS Calibration TEDS Transfer Function TEDS Frequency Response TEDS Commissioning TEDS 11 5/07/2002 Spring Sensors Expo 2002
Slide 12: Commercial Airplanes Airplane Validation Human Readable TEDS IEEE Std 1451.2  IEEE p1451.3    Meta Identification TEDS Channel Identification TEDS Calibration Identification TEDS    Definitions taken from IEEE Std 1451.2 XML Based XML allows the manufacturer to change the contents Commands TEDS  Contains the setup commands 12 5/07/2002 Spring Sensors Expo 2002
Slide 13: Commercial Airplanes Airplane Validation TEDS Size Comparisons TEDS Meta-TEDS Channel TEDS Calibration TEDS Where used Both Both Both IEEE 1451.2 74 96 39 IEEE p1451.3 19 112 40 Comments Plus any bytes required for Groupings. Assumes typical requirements for Physical Units in dot3. These are linear single section conversions. Depending on the complexity of the calibration these can run to 300-400 bytes for polynomial conversions or more if trying to implement a table lookup. This is just a guess. It could be more or less but this should be in the typical range. Plus 24 bytes for each point in the table. Optional Text Based TEDS. Could be very large. Optional Text Based TEDS. Could be very large. Optional Text Based TEDS. Could be very large. Structure not defined. Size unknown. Maximum Transfer Function TEDS Frequency Response TEDS Meta ID TEDS Channel ID TEDS Calibration ID TEDS Generic Extension TEDS Commissioning TEDS Commands TEDS 5/07/2002 Dot 3 only Dot 3 only Both Both Both Dot 2 only Dot 3 only Dot 3 only 90-120 29+ N/A 70 Optional Text Based TEDS. Could be very large. Spring Sensors Expo 2002 13
Slide 14: Commercial Airplanes Airplane Validation IEEE p1451.4 TEDS “Compact” TEDS The TEDS are 256 Bits in size Maximum  TEDS are different for each application  A template is required to describe the TEDS to the system  5/07/2002 Spring Sensors Expo 2002 14
Slide 15: Commercial Airplanes Airplane Validation Virtual TEDS Some applications need to separate the TEDS from the transducer module.   Most consider this an undesirable feature Required for some applications IEEE p1451.3 allows TEDS to be stored external to the transducer module.   These are called “Virtual TEDS” They have the same format as the embedded TEDS 5/07/2002 Spring Sensors Expo 2002 15