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keirf / flashfloppy-osd

On Screen Display and keyboard controller for FlashFloppy
The Unlicense
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A1200 instructions #2

Closed penfold42 closed 5 years ago

penfold42 commented 5 years ago

Do you want me to provide them ?

keirf commented 5 years ago

Yes please, if you could do it and take photos that would be especially great! Hopefully most signals have a convenient pad or component that does not require super skills to solder to. eg. keyboard test points (Rev 2), or fdailing that the keyboard pullup resistors. CSYNC and Green must be available on some lower-pin-count ICs or passives in the video circuit.

penfold42 commented 5 years ago

I’ve already hacked a working version onto my 1200 1D1.

I have my own keyboard intercept project in development and I use a PLCC socket on top of the CIA for KB data and clock. This is probably the easiest way for boards without the keyboard test pins as the pull-ups are underneath.

Video, for now is on the DB23 as I use s-video

keirf commented 5 years ago

Okay that makes sense. Those will be contact points that work generically for any SMT Amiga I would imagine. I also think it would be plausible to solder fine wire direct to the CIA. We don't need a picture of that necessarily. I may mod one of my machines and take a pic of that.

penfold42 commented 5 years ago

I cant see how to edit the wiki so pictures below:

A1200 rev 1.D1 video connections: E260R - red E259R - green E258R - blue E253R - Csync

A1200 1D1 video

The keyboard is a bit more of a challenge - the pullups are on the rear. Here is a pic showing the pins on an upturned PLCC socket A1200 1D1 keyboard

Also is a pic of my actual video wiring: Slide2

I also had a peek at the Rev.2B board on https://www.amigapcb.org/index.php and the video pinouts match 100% The keyboard is nicely available on the test header at CN17. CN17.1 - KB_CLOCK CN17.2 - KB_DATA

keirf commented 5 years ago

Thanks! The wiki is not public editable. I don't know if I can add you but anyway I will add these details in myself not a problem.

keirf commented 5 years ago

Would it have been better to connect to the output side of the 200R ferrite beads? (Unlike the A500 output beads, which are 0R, and it doesn't matter)

penfold42 commented 5 years ago

They’re not 200 Ω I just measured them and they’re 0.2 Ω

I suspect they’re 200 μH

keirf commented 5 years ago

Yes sorry. You're probably right or it's 200 ohm impedance to high freq AC. Either way your hook up is obviously fine. It's all up on the wiki as if this morning. Thanks!