I'm using MQX 4.1, CW10.6, K70 processor. I'm trying to get the MQX Serial-device driver working on UART3. I've enabled BSPCFG_ENABLE_TTYD, and everything seems to be initializing correctly as _io_fopen() get a valid file pointer; However, I am never seeing any activity on the serial transmit pin when I do an _io_fwrite(). I suspect a pin configuration problem. I'm not sure how select the required pins and cannot find any clues in the MQX driver docs. I'm using PTE4/5 for the tx/rx lines to my RS-232 transceiver. Any help would be much appreciated.