TRB245 RS485 recieve problem

[schmoizz]

Hi,
i have a trb246 running where i want to connect an waveshare modbus rtu 8ch io board via rs485.
I’m currently developing a custom openwrt package for it but can’t get the modbus to run.
I’m using 9600 baud, with 8 data and 1 stop bit with No Parity as described in the waveshare wiki with device id 1.
When i send some command over modbus i can see the rxd led on the waveshare board flicker and immediatly the txd flickers.
But ultimately the data is never recieved in my c programm.
I can’t really inspect anything.

Can’t i use the rs485 in my on programm? Or do i need to be aware of any special settings? I can’t really find a documentation for this in combination with the provided sdk.

Thanks for your help

[Matas]

Greetings,

As custom-written SDKs & packages are quite advanced, and are out of our technical support scope, I’m not able to comment much or give you good suggestions. I may try to reach out to our R&D to see if they’d be able to help, but it’s not a guarantee.

Some additional information, that may come in handy, is that we have a Wiki for compiling the custom SDK that you’re building: RUTOS Software Development Kit (SDK) Instruction - Teltonika Networks Wiki

@schmoizz

Can’t i use the rs485 in my on programm?

As the TRB has RS485 support, in theory, you should have no issues utilizing it. The issue may derive from something else.

Regards,
M.