Advantech Adam 4561 to 4019 not communicating

[PaulG.]

Having a problem communicating with an Adam 4019+ through an Adam 4561 USB to RS485 Converter. VISA seems to see the converter OK, but all it is just a converter to communicate with the 4019. I'm getting nothing.

I put it in INT mode to set the protocols to default 9600 8,1, none. When I try to access it in Adam/Apax.net I get an "Unable to send command!" error and nothing else.

This is a Modbus component and I've successfully used Adam/Apax and Modbus in the past. This has me stumped. Any insights? Thanks.

[walker.p]

Hi PaulG,

Have you been able to reproduce this on another computer? I'm thinking it would be good to see if we can isolate the issue to be with the hardware itself, or with the cable that you're using to connect them, or with the computer. Swapping through these would give us a better idea of where to troubleshoot.