AccessPort is a port debugger used to debug serial port.

It provides you to send or receive data through serial port.

This program is a tool for debugging computer connections with peripheral
devices using COM ports such as modems, mini-ATS and projectors. It can
send data through COM ports, receive data from outer devices through COM
ports, and has port indication. It supports connections at the standard
speed of 110-15200 kbit/s and commands from COM port program control.

The newest version add serial port monitor, it could caputure all of data
transfer through serial port.

Serial Port Monitor Debug