Modbus via USB

[jassa]

Hi,

I have setup a Connect as a Modbus RTU Master and configured the address etc as per the slave manual.

I'm using a RS485 > USB cable that came with the Slave. I can use that cable to plug it into a windows machine and use the Slave's software to configure the slave with an address etc.

By default, the device_path in Pictory is /dev/ttyUSB0. When I follow the steps here https://revolutionpi.com/tutorials/linu ... ad-finden/ it gives me a device_path of /dev/ttyUSB3

I have followed the steps at https://revolutionpi.com/tutorials/modb ... -turorial/ but every value in piTest comes back as 0 so I'm wondering if it is even recognising the slave? Is there a simple way to test that the slave is being recognised?

[giuseppe]

Hello jassa,

check the links below:
Modbus Checklist
RS-485 Checklist
Modbus-RTU Communication

Best regards
Giuseppe Pagano

[herringbur]

I can plug it into a Windows system and use the Slave's software to configure the slave with an address and so on.