Two dead LK201 keyboards

Pete Turnbull pete at
Sat Dec 28 04:25:14 CST 2019

On 28/12/2019 01:46, Paul Koning via cctalk wrote:

> I can get one and test it with an Apple keyboard, but that doesn't sound right.  There aren't enough wires on a USB connector to allow you to speak the PS/2 protocol.  And there are PS/2 to USB adapters (for old keyboards) that are the same size; clearly the old keyboards don't speak USB.

Enough wires?  +5V, ground, clock, data vs +5V, ground, D+, D-

Those old adapters are definitely just passive wiring, and were commonly 
supplied with dual-standard mice.  That's why they're green.  I worked 
in the IT department of a large university and it caused a lot of 
confusion back in the day when they were common, when people expected 
them to convert any keyboard or mouse to PS/2, and found they didn't. 
They only work with devices that inherently support both protocols.

Pete Turnbull

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