10 Jul
2014
10 Jul
'14
11 a.m.
The model M
was available with several different connectors. Most of the
I know of 2 (5 pin 'type A' DIN, 6 pin mini-DIN). What others are there?
> original AT (5170) had a 5 pin DIN connector that looked the same as the
> 5150/5160 keyboard connector, but they are elctrically very different. Actually, I seme to recall tht the signals are the
same -- clock, data,
+5V, ground. And on the same pins on both the XT and AT. The 5th pin,
origianlly a reset outptu from the PC to reset the keybaord at power-on
was, AFAIK, never used.
Hwoever, the serial protocol is very different betwee nthe XT and AT
keybaords. So while the clock and data are on the same pins, they
keyboards are not compatible.
The AT keyboard had LEDs for num/caps/scroll lock from the first. I
don't think there was anything in the 5150 keyboard protocol to handle
them, so they would have had to do something different anyway.
Philip.