The H747 has 8 regular serial ports and a "low power" LP serial port.
Ports 1,2,3 and 6 are the same. Ports 4,5,7,8 don't have synchronous features
(which matters not to me).
Port 1 is connected on the board to the ST-link processor to provide the VCP (virtual console port) via USB.
Tom's Computer Info / [email protected]