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Old 8th Oct 2018, 6:14 pm   #15
Maarten
Dekatron
 
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,185
Default Re: 486 PC. Keyboard problem.

For completeness sake: there are basically 4 types of PC keyboard.

- PC and XT: 5 pin DIN, unidirectional protocol
- AT: 5 pin DIN, bidirectional, same protocol as PS/2
- PS/2: mini DIN, bidirectional, same protocol as AT
- USB: similar protocol but entirely different hardware layer

AT and PS/2 are always interchangeable with a suitable adapter cable.

Some USB keyboards might have hardware support for an adapter cable as well, but only if it was explicitly built in.

Some mid to late 1980's aftermarket keyboards might sport a switch in the back or on the bottom to switch between XT and AT modes.
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