Hello Skyyuzhang,
Thanks again for sharing your working project on GitHub. I built it up and tested on inexpensive STM32F103s with known good SN65HVD230 adapters and had immediate success. Compiled with gcc 7.3.0 on Windows. I’ve documented it here https://www.rcgroups.com/forums/showpost.php?p=40932635&postcount=16
Thanks so much,
George
