Guru
Joined: 24/12/2017
Location: AustraliaPosts: 1694
| Posted: 05:41am 18 Feb 2024 |
The first circuit plugs into the PS2 connector on the PicoVGA (I Believe) which does use 5v levels but...
I should give while I'm only so far behind.
Which circuit do you want to use?
The first one shows something which is separate and connects between the keyboard and the PicoVGA. The level shifter in the PicoVGA uses 10k pullup resistors so that should limit any input current to safe levels so a level shifter should not be needed.
It could also be fitted internally without the socket and PS2 lead the same as the second one shows. This means surgery on the PicoVGA board.
The second one is meant to be fitted internally. This also means surgery on the PicoVGA board.
A third option may be to use Peter's "CMM1.5" firmware which means you can plug the keyboard into the Pico's USB socket via a USB A to C adapter. I have not followed it closely enough to know if this is viable.
Personally, I would just buy a PS2 keyboard. I bought one from an op-shop for a couple of dollars.
Bill