LOOPBACK TEST for RS232

[Gilfoyle]

Hi everyone

I try to connect a hardware by using the Rs232 port on CompactRIO 9025. But I want to be sure that the communication is working correctly. And then I will examine the codes that I wrote for the hardware.

For this I connect to the CompactRIO with Ethernet cable. And I connect a RS232 cable to the port on cRIO. I shorted 2-3 pins of RS232 cable and then I open VISA Test Panel in MAX.

When I query the *IDN?\n command, I get the error "VISA time out"

Also when I push the button "Read Status Byte" on the same tab, I get this error "Unable to start operation because setup is invalid (due to attributes being set to an inconsistent state) "

So, any idea?

[Minions]

As you have the Transmit (Tx) of the RS-232 communications port tied to its Receiver(Rx), all you should be looking for is the echo of what you want to transmit.  Send a character 'A' and verify that an 'A' was received.  It will not be able to respond to any other commands in this fashion.