Ways of Connecting
Back to Back SIMs over UART or RS485/422
If you copy the project and modify it to be the “slave” side without the need for the polling timer, you can now use two SIMs back-to-back!
Using the UART, connect power and RX<-TX, TX->RX. On Gen5 SIMs (SIMx52, SIMx62) you can use crosswire RS485 by connecting the two grounds and wiring AB to YZ back to back on the two SIMs — make sure you have Half Duplexand Termination selected on both ends.
Single Ended to a Terminal
You can also just use the project and connect to a PLC or external Modbus slave device over UART or RS485. The SIMx52 and SIMx62 Technical Reference Manuals (TRMs) on the mySerious.com portal have detailed instruction on how to connect the RS4xx port.
