I confirm what Darrel's said. There's a lot of things to do before it work as expect.

I already suggested awhile back to build a PS-2 sniffer and log the whole data exchange from the boot... to the end. It's more than a stupid BIOS setting. In fact.. you have to confirm your Keyboard is there, and it's self test is passed.

Not that hard.. not that easy.

If you have any protocol analyzer or digital storage scope (PoScope, Bitcope, USBee) that will be easier.

For safety sake, you can't use Shiftin/Shiftout AS-IS. You need to toggle TRIS instead of trashing a pin to high or low.

Note: A PC may work slightly different from a Laptop.

This said.. this should be enough food for thought