Hello,
I am working on establishing communication with a pc, the pc isn't standard but has a gpib bus to communicate with.
My goal is to read this pc memory from address that I choose using this pc gpib commands.
So far I have tried to use gpib-usb-hs+ to received the data from the memory but no success.
So I moved to tms9914anl and had a great success receiving the desired data, but I met a weird problem. I can read the memory of the pc only when I have gpib-usb-hs+ on the bus (tms9914anl, pc and gpib-usb-hs+) as monitor/in capture mode/analyzer.
Otherwise I don't can't receiver any data.
The data I send to the pc is:
UNL - Command
MLA18
00 - Data
02
00
00
80
00
UNL - Command
MTA18
(sending 0:00-without it nothing works) - Data
(-starting to receive data over the bus)
Xx
Xx
Xx
Xxx
..
..
..
UNT-Command (data will keep flowing until ATN rises a d UNT sent)
My question is what the gpib-usb-hs+ does on the bus in capture mode that helps me to read the pc.?
We isolated all the pins in the gpib-usb-hs and found that it's something related to handshake.
