View Full Version : Keyboards compatible with 3v

Oldbitcollector (Jeff)
03-31-2012, 04:24 PM
I've got another Quickstart module in the works which incorporates a PS2 connection.

Did some testing to determine if it was possible to power typical PC keyboards at 3v.

I thought I'd share my results.

{Test unit was a Quickstart with QuickAdapter to PP Proto Module with breadboarded PS2 jack.}
{Standard PS2 demoboard type circuit used.}

PS2 PC Keyboards
MICRO Innovations PS2 Keyboard YES
Memorex TS1000 PS2 Keyboard NO
IBM 1395300 PS2 Keyboard NO
DELL PS2 Keyboard 04N454 YES
Microsoft Ergonomic PS2 Keyboard NO
HP SDM4700P Ps2 Keyboard YES

USB Keyboards w/PS2 Adapter
Dell USB Keyboard L300 NO
SOFT Key Keyboard USB F21TQ NO
Microsoft USB KC-0405 YES

Success rate with PS2 keyboards appears to be around 50%
The successful keyboards were the more common (for me) PS2 keyboards.


03-31-2012, 07:10 PM
Awhile back I bought a Dell PS/2 external numeric keypad (model 86004) -- I've never got around to hooking it up but I did note that the Holtek 48R06A-1 CPU they built it is explicitly compatible with 3v3 thru 5 V power.

Toby Seckshund
04-01-2012, 01:46 PM
I too tried to get away without a 5 Volt rail, whilst using a keyboard, and possibly mouses. About 2/3 of the keyboards were happy but only about 1/3 of the rodents were.