Help: can not communicate with TDS210 through RS232-RS232

[Dennis_Knutson]

Changing the timeout value is not going to help at all.

When you get this error, there are a few things that could cause it. One is sending an incorrect command or the correct command but incorrectly terminated. In this case, you are sending a valid command with a line feed (\n). Verify that the instrument is setup for this terminator. Another possible cause is a mismatch in com settings. Make sure the instrument settings match what you have set the pc's com port to. You also want to make sure you are using the correct type of serial cable. There are two major types - null modem and straight through.

[navy1979]

Thanks Dennis.

My cable is straight through. I Have now changed it to Null moden(2-3,3-2,5-5). Now the MAX viRead and viWrite is as follows:

                  TDS210 Setting: Baud rate-9600; Parity-None; FLow control:None; EOL string:LF;

                  MAX Setting:      Baud rate-9600; Data bits-8; Parity-None; Stop bits:1;FLow control:None

 
                  viWrite: *IDN?\n
                  viRead: TEKTRONIX,TDS 210,0,CF:91.1CT FV:v1.17 TDS2CM:CMV:v1.04\n

But when I run program from Tektronix TDS 200 1000 2000 Series examples, problem occurs:

The setting is as follows:

                  TDS210 Setting:Baud rate-9600;Parity-None;FLow control-None; EOL string-LF;
                  Acquire waveform program setting: Baud rate-9600;Parity-None;Stop bits-1;FLow control-None

The fLow control setting in the TDS210 automatically changes from "None" to "Hard flagging" when I click RUN. Then error as the attachment. Please help.

[Dennis_Knutson]

That's the same error you reported in your first post. The good news is that the initialize function seems to work but you get this error during the autozero. I'm not at all sure what could be causing the reference to appear invalid. Sorry.