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On building an A500++

Commodore Amiga 500 Plus

In the 1980s, Commodore made a newer version of their very popular Amiga 500, called the Amiga 500 Plus. It added a few things, namely newer versions of Kickstart and Workbench — both 2.04, 1MB of Chip RAM, and a motherboard-based Real Time Clock. The RTC was battery backed up, and is responsible for VARTA battery leaks. These batteries leak base (not acid, like most people assume) and this eats the PCB causing failures. There were also minor improvements of the custom chip sets, introducing the Enhanced Chip Set.

Enter the A500++

The A500++ is a newly designed circuit board that is a direct copy of the Amiga 500+ PCB with a few minor improvements. This circuit board can be bought off a gentleman in the UK. It is a beautiful shade of purple and really is a work of art by itself.

Ordering the parts

It takes almost (90) different line items totally approximately (400) parts to recreate a modern Amiga 500+. These parts are generally ordered from Mouser, and cost in the neighborhood of about $150 or more. You still need to recover CPU, custom chips, RAM chips, and other parts from an original A500+. Or Ebay. Or Amibay. This project is a ton of work and while it’s mostly through hole, your patience will be tested with hundreds of hand-laid parts like capacitors and resistors.

No pick and place or wave soldering for me!

A500++ Parts ordered from Mouser

It’s really amazing at how many different parts it takes to recreate a 1980’s computer. Just look at all those. Even the image fails to give the true picture. Just bags and bags.

I’ve put about two nights of soldering in. I’d estimate that I’m in about 4 or 5 hours so far. I’m going for a “good job” versus a “fast job.” There are plenty of mistakes to be made here, and I don’t need to be blowing up any of the expensive custom chips I’ve needed to order separately.

My current state:

A500++ Day Two

Links

The community BOM is located here. It is a little more updated and clean than the official one. See: https://docs.google.com/spreadsheets/d/13xq2P7Ha_PA6r3vfPw77Q9PaSZYWncYfNpqhrwdvhaY/edit#gid=0

Fairly active Discord is here.

Email contact for buying a board is here: a500plusplus _ a t _ outlook.com. It costs about 60 GBP to the continental US.

keith

Amateur Electronics Design Engineer and Hacker

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