Tail485 bidirectional communication
enricobilla last edited by
I've been working on a project recently with an Atom Lite and a Tail485. I'm trying to use those to read from a Modbus RTU sensor through RS485.
The problem I'm having is that I'm not able to achieve bidirectional communication with the Tail485, at the moment I don't know whether I cannot send or receive data. All I know for sure is that the modbus sensor is not sending any data after the request (the sensor is working with another transceiver). For the tests I used multiple micropython libraries for Modbus but also an Arduino library (even using an Arduino Uno), and I always get the same error: no data received.
I'm not able to test it thoroughly right now because I don't have the tools to debug the RS485 signals, but I will in the next days.
Looking at the datasheet the IC used (SP485) uses two pins (DE-RE) to control the flow of data from UART to RS485 and vice versa. That pin tho is not exposed on the Tail485 module (there are only GND 5V TX and RX), so I was wondering how the flow control is implemented on the module (if there's any). Otherwise, can the module exclusively send (or receive) data?
Thank you in advance for your help!