I'm using SR830 for an experiment and I'm trying to set the amplitude of the sine output when the lock-in works in internal mode and I have the following problem: the lock-in doesn't understand the decimal point, it reads the first non-zero digit and sets the amplitude (e.g. 5 instead of 0.5). I've used the command slvl, as it is said in the manual. I've used the drivers for GPIB from the national instruments site and I've just made some changes because I'm using a serial port. I have also used the command for setting the frequency just before this one and I don't have a problem with it. It cannot be a problem from the lock-in, because everything is normal when I'm controlling the lock-in with other programmes.
I don't have an SR830 to test, but the manual suggests that what you are trying to do should work. Some questions that may give some clues to the problem: Have you read the status bytes to see if the SR830 has generated any errors? Is it possible that the letter "o" was sent in place of the numeral "0"? Was the proper termination character (\n) or (\r) sent? Does the computer use a comma as a decimal separator? (Some parts of the world use commas and LV may or may not use the local settings, depending on how the preferences have been set.) Can you set the frequcny to 0.5 Hz? Can you send the command successfully from a terminal emulator?
First of all, thanks a lot for your advice. I have tried everything that you have suggested and it's still not working. I thought that the problem could result from the format of the number, but I'm not really sure. I have already tried all the possible combinations and the result is that when I change the format, new problems come up. Anyway, if I manage to make it work somehow, I'll let you know. Thanks again!
Why don't you post the code you've written to set the amplitude. Someone can look at it and compare it to the 7.1.1 code and see if you've done something wrong.
