FDD Interface for Commodore Amiga CD32

[@rt]

Minus a 74LS03 chip which hasn’t been sent by the seller yet

https://photos.app.goo.gl/JVvFYIbSjg9SgEMM2

[Halcyon]

This is something you've built? I don't know anything about the Amiga CD32... it didn't have a drive interface already?

[@rt]

The CD32 only has a 2x CD drive, but his connects to the rear expansion port (when I make ribbon cables for the edge connector).

[Bruce Abbott]

Looks familiar...

http://aminet.net/package/docs/hard/cd32_floppy

[@rt]

Funny to find the author here

It does have 74LS01 to replace 74LS03 now (just has a different pinout),
and one of these pics show how I mangled the design to use LS240 in place of LS541.
I lost the Schmidt trigger inputs in doing so, but also noticed not every input for the original circuit (address bus) had them.

[@rt]

[Bruce Abbott]

Well done!

Your video brings back some fond memories...

How did you connect it to the CD32?

[@rt]

Hi Bruce
I had a spare SX-1 adapter that provides 3 of the card edge connectors.
One is destroyed by the blower, one is used to connect this interface to the console, and the other is still waiting for my next attempt at salvaging.
For the one in use here, I lost a few pins including some upper address bits I think, just none that were needed for this circuit.
I might have had a go at a 68030 accelerator as well if the connector had come off in one piece.

All of the signals you got from ROM socket & test points are also at the edge connector of course.

[@rt]

The floppy interface address filtering provides parallel port read and write address filter for free,
so only a couple more chips for parallel port decode:


I’m going for full Centronics parallel port next, and full serial port (which will require the whole 7 chips again.

[BubbaMc]

Nice, tidy implementation.

So is your CD32 effectively an A1200 now?

[@rt]

Well they kinda were expanded already because I have SX-1 modules for them
For this project I'm planning next to use an A1200 Gayle chip for IDE interface.