TMS320F28335: 上电时序正常，但是串口功能（SCITXD）无法正常启动，需要硬件手动复位后，功能才能正常，请问是哪里的原因？

你好，参考下工程师的回复：

Thanks for your question. So the most common reason for this is initializing the SCI module too quickly in the configuration code. For example:

Let's say you initialize the SCI module while the RX pin is still settling: you will get errors and issues in the SCI.

So I recommend initializing the SCI after the SCI RX pin has settled (maybe add a 100us delay before allowing the SCI module to exit reset).