Part Number: MSPM0-SDK
Other Parts Discussed in Thread: MSPM0C1104, MSPM0G3507
Small-package MSPM0 devices often run into hardware UART count limitations due to pin constraints. When you need more serial interfaces than the on-chip UART modules can provide, a software-based UART is a good fallback. This thread shares a timer-driven software UART implementation for MSPM0 that emulates both TX and RX using ordinary GPIO pins. It supports half-duplex operation with automatic baud-rate detection — no manual configuration needed — and compensates for ISR latency to keep sampling timing accurate. The implementation has been tested on MSPM0C1104 (up to 230400 baud) and MSPM0G3507 (up to 460800 baud).