I'm wondering if anybody has any information or links to information about programming a dos tsr in VC++?

I'm trying to write two programs: one that captures all text that the console outputs and sends it to an lcd display through the parallel port, and another which will translate input from a 10key numpad through a serial port as text (ie. "1ENTER" = "a" "11ENTER" = "b" "2ENTER" = "d" etc). Both need to be tsrs...I can program everything (the keyboard stuffer, the hardware interfaces, etc) except for the tsr part.

Any advise is greatly appreciated! Thanks