I also have a HP436A and try to make the GPIB work. After search on several websites, I could not find any example, therefore, I spent two days and figured out this problem. Here is the right GPIB command sequence :
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Interactive Control
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Type 'help' for help or 'q' to quit.
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GPIB0: ibdev
??? enter board index: 0
??? enter primary address: 13
??? enter secondary address: 0
??? enter timeout: 10
??? enter 'EOI on last byte' flag: 1
??? enter end-of-string mode/byte: 10
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ud0: ibclr? <----------- use this to turn on remote LED, required.
[0100]?? ( cmpl )
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ud0: ibwrt "9A+I"? <---- this means: set RF power unit to be W
[0100]?? ( cmpl )
count:? 4
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ud0: ibrd 14????? <-----read 14 byte data as ASCII
[0100]?? ( cmpl )
count:? 14
50? 4c? 41? 20? 30? 39? 39? 30????????? P L A?? 0 9 9 0
45? 2d? 30? 39? 0d? 0a????????????????? E - 0 9 . .
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Details about the "PLA" can be found on page 3-19, HP436A operating and service manual.
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I use a NI GPIB-USB-HS adaptor, run on windows 10, with NI VISA (2022) installed.
With NI MAX scanning, I found the address=13 for HP436A.
With NI MAX interactive control, I tried above sequence.
When you implement above sequence with C or python, the timing is important. Between ibclr to ibwrt, it needs about 0.3s, between ibwrt and ibrd, it needs at least 1.2s? (1.2s is the worst case according to the manual).
Lin
