Issue :
-> Using a TTL(uart) to RS485 converter which was connected to Tx0 and Rx0 of the mid carrier board. On using Serial1.write() to send the command frames to the RS485 based IO module , I was successfully able to control the outputs. But when I tried sending the command to receive the input data, the transmission worked effortlessly but on Serial1.read() I was unable to get any data.
Hardware Setup:
-> Portenta X8, Mid Carrier, Hat Carrier, Waveshare 8CH Input & Outputs, USB-TTL converter/debugger
Hardware Connections:
Steps Taken:
-> To test if any data was being received on the M4 serial line ,I used a USB to TTL converter and connected it to the same serial line with Tx0 and Rx0 to check if issues was with relays or the Rx of portenta(though the relays have been thoroughly tested)
Code Used :
-> I additionally added serial commands to write the data that was being received on the other uart. But on executing the script it was observed that the relays were able to send the inputs as observed on the usb-ttl device on a python script, but the M4 was giving no data thereby receiving no inputs.
-> Same thing was tried with other carrier board like Hat Carrier but the results were the same.
Expected Outcome:
-> Receiving the input status whether it is 0(low) or 1(high) was expected. Serial writing the commands and then receiving the frames from the relays to portenta was expected behavior.
Actual Outcome :
-> There are no inputs that can be seen on Serial1.read() not even a single character is being received. This was verified using Serial.print() as well as using Serial1.write() to write the received data on a separate UART line.