Bootable Keyboard Tester

Bootable Keyboard Tester cover

Summary

This is a bootable keyboard tester for IBM PC-compatibles. It fits in the bootsector of a hard disk or floppy disk. It can be used when trying to diagnose stuck or dead keys. When a key is pressed, the background of the corresponding on-screen character turns white and the foreground turns black, when it is released the character's background will return to black. However, the character's foreground will remain white to indicate that it has been pressed in the past.

Downloads

keytest.bin: 512-byte floppy bootsector (version 1.0, 512B)
keytest.asm: NASM source code (version 1.0, 732B)