hi.
Im trying to design a custom USB keyboard to use with my PDA running mobile 5.0.

there are 5 push switches being fed into a pic ic, through some manipulation these 5 switches can hold 32 different possibilities which i'd like to use as 32 different key presses as a standard keyboard would.

All of the OTG purpose built keyboard controllers i have found are compatible with a standard keyboard matrix, usually 9x18.
Does anybody have any ideas how i would go about interfacing the output of the pic to the keyboard controller?

i could output to say a 6x6 matrix, but because there is no physical closing of the contacts how would this work? (use some hall effect ic(???)) or would i need to to use a usb interface chip and a seperate processor?

Any direction would be greatly appriciated.

 

As we've told you before, get a USB keyboard and strip the insides out of it - it doesn't take much thought to realise you can easily fit a 6x6 matrix where a 9x18 one is supposed to go.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

i do appologise, but the thing i'm having problems with is a keystroke is detected by the controller when a button physically pushed to make contact, and so is a grid with a steady current and 200 odd breaks in the circuit. The pic will just be sending a positive pulse. .

 

yeah sorry im sorted. just asked without thinking it through.