visa read in loop

[lucas26]

Hi,

I exchange data with a FT2232C on a board, then through USB.

After 8 characters command sent the board, the board sends an acknowledge  = 3 characters = *1Y.

If done one by one (see R-W single FT2232.vi) :  it's OK, acknowledge is received after each command, which means that overall transmission is good.

But when a packet of command is transmitted,  half acknowledges are not received : see R-W loop FT2232.vi.

This a SW problem because using a scope, all data at input and output (RX & TX) of the FT2232 are present, which means that VISA WRITE in the loop is OK

But VISA READ seems to have a problem ???

Thanks for your answers !

[crossrulz]

First of all, I would recommend using the Configure Serial Port inside of the VISA palette.

I also noticed you greatly  decreased your timeout for the multiple command.  I think the default is 10seconds and you set it to 500ms.  The single command did not do that.  So try not setting the timeout.

I have also known instruments that need additional time to set something up.  You may want to add more delay in your FOR loop.

[MarcoMauri]

Did you try to check with a serial port sniffer?

Moreover: try placing the wait vi after the reading and increase the ms to wait until everything works (hopefully) as expected.

Regards,

Marco