Downloaded your script and ran it on a Windows 7 box, and I see FF010003005F630A going out the port.
Your problem is probably one of:
- Bad serial monitor. There aren't many software serial monitors that actually work on Windows 7. I use "Advanced Serial Port Monitor", which does work.
- Serial port permissions. Run your script under a shell that you started with right click -> run as administrator.
- Wrong serial port. Start device manager (under control panel) and make sure you see COM1, without any yellow or red warning symbols about the device state. This one seems likely. It's unusual (not impossible) for windows to assign COM1 to a USB to serial device. I bet your serial port is actually COM3.