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newbe keyboard problems — Parallax Forums

newbe keyboard problems

Areal PersonAreal Person Posts: 197
edited 2007-11-01 00:04 in Propeller 1
Hi,

Does the keyboard absolutely require 5vdc ?
If so, whats the simplest way to provide 5vdc ? I've read the 5vdc thread, but
what's the simplest way to do it ? I'm new at this stuff.

None of the keyboard lights come on, I've read several threads, I've tryed reversing
clock & data pins, I've double checked my wiring & resistors. I know the Propeller chip is ok as well as my
simple spin code is ok.

It should not be this hard to hookup the keyboard. I've been working all day on it confused.gif

My VGA monitor works fine on the breadboard, I'm not providing it any additional power.


Please help, I'm lost on what to try, I've never hooked up anything over 3.3vdc to my propeller.

I think I can just use a resistor with 5vdc? what size ?


Thanks,
-Areal



▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
I have a tree growing out of my head, but

what do you expect ? I'm a programmer.

Post Edited (Areal Person) : 10/29/2007 7:37:53 PM GMT

Comments

  • NewzedNewzed Posts: 2,503
    edited 2007-10-29 19:36
    Put a 5VDC regulator in front of the 3.3VDC regulator.· The output of the 5VDC regulator should feed the input of the 3.3VDC regulator,
    and should also feed pins 3 and 4 of the keyboard connector.· The two pullups on pins 1 and 5 on the keyboard connector should go to 3.3VDC.

    Sid

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Yesterday is history, tomorrow is a mystery, and today is a gift.

    That is why they call it the present.

    Don't have VGA?
    Newzed@aol.com
    ·
  • Mike GreenMike Green Posts: 23,101
    edited 2007-10-29 19:40
    Areal Person,
    When in doubt, use existing working hardware as a reference. There are schematics for the Propeller Demo Board and the Propeller Protoboard that show how to hook up a PS/2 keyboard connector to a Propeller. These boards work with PS/2 keyboards and mice. If you hook up your PS/2 keyboard the same way, it should work too.
  • Areal PersonAreal Person Posts: 197
    edited 2007-10-29 19:51
    Ok, Thanks ! I'll try these things.

    I see, the 5vdc is required, Ha.. Ha... well, it's my own fault, I guess
    I got stuck because I've not used 5vdc before, I hope I don't fry it [noparse]:)[/noparse]

    Thanks, I'll let you know how it turns out.
    -Areal

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    I have a tree growing out of my head, but

    what do you expect ? I'm a programmer.
  • Graham StablerGraham Stabler Posts: 2,510
    edited 2007-10-29 21:42
    When you are working with 10,000v that's an excuse [noparse];)[/noparse]

    You won't fry anthing if you include the resistors shown on the schematic.

    Graham
  • deSilvadeSilva Posts: 2,967
    edited 2007-10-29 23:20
    We connect a wallwart and - hey presto! - 110V AC becomes 5V DC. This is black magic, as we bought it from the store.
    But can our simple resistor do that trick? Be calm - you also bought it from the store smile.gif
  • kevin101kevin101 Posts: 55
    edited 2007-11-01 00:04
    Newzed is right. A simple 5vdc regulator will get less voltage spikes than an unregulated wall wart. Its also cheaper, like a buck fifty for a 7805 voltage reg. you could also get two variable voltage regulators and set one for 3.3v and the other for 5v, but thats kinda complicated.
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