Major c64 project, any tips? - Page 1
Forum section: electronics / projects

author: Ampera
author_rank: Super Contributor
timestamp: April 03, 2015, 01:01:16 am
content: My dad had TONS of commodore computers, and he currently has 3 disk drives. One of them is not working, but all the old commodore drives had 6502 CPUs in them to control IO and the actual drive part. Since it's foobar, I've decided to make a C64 Handheld or laptop system with, 1. a commodore DIN serial port to hook up a floppy drive 2. a built in SD card reader to load roms off of, 3. to have user, cartridge, and tape edge connectors to be as compatible as possible with commodore peripherals. I just want to ask if anyone has any ideas of where I should look on designing it. I have access to modern parts and EPROMs so i should be able to make it more compact than it normally is.Should I look at what other people have done, or just base something off the C64's schematics? I am not asking for a planned out detailed explanation of how to do it, just where I should get started.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 03, 2015, 01:05:09 am
content: http://en.wikipedia.org/wiki/C64_Direct-to-TV

author: Ampera
author_rank: Super Contributor
timestamp: April 03, 2015, 01:08:36 am
content: Cool, but I'm afraid custom ASICs and SMD components (Except for a few things) are beyond my reach. Thanks anyway.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 03, 2015, 01:34:28 am
content: The C64 is nothing but ASICs. For one thing, it doesn't use a 6502, but a 6510. A project in itself if you want to get that to work starting with a 6502.The 6526s are proprietary and are 6522s on steroids. The sound chip is old-school hand-tweaked silicon doing analog stuff with a digital process.The video chip is quite complex as well.The "bus master" PLA is also a little nightmare.You are better off just going with all the work that's already been done, unless you want to reverse engineer the whole thing yourself.It's not a trivial computer even though it's 30+ years old.

author: daybyter
author_rank: Frequent Contributor
timestamp: April 03, 2015, 01:37:07 am
content: I think lemon64 and forum64 are places, where you can find people doing such projects.Like:http://www.benheck.com/commodore-64-original-hardware-laptop/

author: BloodyCactus
author_rank: Frequent Contributor
timestamp: April 03, 2015, 02:06:17 am
content: The C64C motherboard is small enough you could make a case for it, keyboard interface etc.

author: Ampera
author_rank: Super Contributor
timestamp: April 03, 2015, 01:23:48 pm
content: my dad DOES have one, but I am not sure he'd be willing to let me mutilate it.I see what you are saying, and it's mostly custom stuff. I have looks at pintrest stuff and other guides where people use the 64C board. And by custom ASICS I meant I can't pot my own chips never mind design them. I am sure I could find most of the chips intended for repairs that people ripped out of foobar machines. As for the 6510, I will see about that. I need to check if they are interchangeable or not.I swear this forums needs a sheepish emoticon.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 03, 2015, 02:06:25 pm
content: Quote from: TwoOfFive on April 03, 2015, 01:23:48 pmWhat's to check? It has a 6 bit IO port that the 6502 doesn't, and a three-state bus that will require at least two 245s to emulate with a 6502 plus all the timing problems.https://en.wikipedia.org/wiki/MOS_Technology_6510

author: Ampera
author_rank: Super Contributor
timestamp: April 03, 2015, 02:34:15 pm
content: Didn't know that. Now I do.