RS232 intermittent failures

[Rimfire]

I am writing software to communicate with a telescope mount. Most communications work just fine over RS232, but occasionally a command will just not work. The odd thing is that if I put the vi into trace mode and slow everything down, the command works just fine. As far as I can see, the number of bytes written, as read from the VISA write block, is identical. I suspect that the problem is not in the VISA setup but I'm at a loss as to just what to look for. Does anyone have any suggestions?

Thanks,

Dave

[Henrik_Volkers]

I assume your telescope mount uses a small µC (Pic/atmel...) with a simple UART programming and close to no or one byte buffer.

Two ways that solved my problems:

Use a lower baud rate  or if that is not possible

send your string as single characters with a 1-5ms delay inbetween. (But check about the termination characters, don't send them after each charater 😉 )