Hey everybody,
I am aware this topic was discussed to some extent in other threads, but after reading them I was still not able to find a solution to my issue.
I am trying to connect to a Signal Recovery 7225 Lock-in amplifier through RS232 serial communication. In NI MAX, I set all parameters according to the manual, 9600 bauds, 7 (or 8, neither works) data bits, 1 stop bit, even parity, DTR/DSR Echo, terminator for both read and write on 'termchar', which is set to 'carriage return' (\r).
According to the manual, the command 'ID' (or also 'ID\r') should have the amplifier respond with its ID '7225'. However, when I hit the 'query' button, I seem to be able to send the command as I get echo-ed back 2(or 3 if I used 'ID\r') bytes, however, the read fails after timeout expired (0xBFFF0015) as the instrument does not respond, so I assume the command settings are still not quite right? In the NI I/O trace also codes 0x08361E38 and 0x038793C0 show up, which I was unable to find anywhere on databases. I did install all NI-VISA USB/RS232 drivers, according to the instrument documentation it does not require one of its own.
Perhaps someone who made a similar instrument work knows what settings I am missing, or perhaps a different mistake.
I am attaching you all material that could be helpful.
Really really really would appreciate a tip or two.
Best regards,
Hannes
P.S.: In the attached instrument documentation, serial communication is referred to in 6.3.02 and following, and the appendix lists all commands alphabetically.