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GPIB
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This is an example capture of some GPIB traffic on an HP 1631D LA/scope.

Details:
http://www.rudiswiki.de/wiki9/SigrokDecoderGPIB
https://github.com/rudi48/sigrok-gpib


Logic analyzer setup
--------------------

The logic analyzer used was a Saleae Logic16 clone (at 500kHz):

  Probe       GPIB
  -------------------
  0           DIO1
  1           DIO2
  2           DIO3
  3           DIO4
  4           DIO5
  5           DIO6
  6           DIO7
  7           DIO8
  8           EOI
  9           DAV
  10          NRFD
  11          NDAC
  12          IFC
  13          SRQ
  14          ATN
  15          REN


Data
----

The following is happening on the GPIB bus in this capture:

 - Controller sets the GPIB to UNLISTEN and UNTALK (neutral state)
 - Controller sets device with GPIB address number 4 to LISTEN
 - Controller sends command 'ID LF+EOI' to device with GPIB address number
   4 (request identity string)
 - Controller sets the GPIB to UNLISTEN and UNTALK (neutral state)
 - Controller sets device with GPIB address number 4 to TALK
 - Device with GPIB address number 4 sends the ID string 'HP1631D+EOI' to
   controller
 - Controller sets the GPIB to UNLISTEN and UNTALK (neutral state)