Other than just "Keyboard Processor", is it a 6502 plus 6532 in one package, or something like that?

Someone who does really know what he's talking about told me there was a 6502 in the Amiga. I know Amigas pretty well and found this very hard to believe. But then he said it was the keyboard processor. I never paid close enough attention to the keyboard, I guess.

Who made it? It's not in the datasheet archive at http://6502.org/documents/datasheets/, and it's not in my 1987-88 Commodore product guide that has oodles of 65xx ICs.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I found this link which confirms it as a keyboard micro controller but no data sheet. A pin out is shown however.

http://www.amiga-stuff.com/hardware/6500_1.html

Wikipedia also has it listed but no details.

_________________
Regards, KM
https://github.com/floobydust

All the ones I have say CSG, which of course is MOS Technology after Commodore bought them.



That's very interesting!

It is, here: http://archive.6502.org/datasheets/mos_ ... t_1986.pdf

What an interesting chip. I'd never heard of it before. Now, if only someone still made one like that with an equivalent 6502, 6532, and 6522, I'd have a project for it. I probably couldn't afford it in low quantities, though.

There are the 65134 (65c02-base microcontroller) and the 65265 ('816-based microcontroller). They're quite nice, and they're being made today, but unfortunately their onboard ROM is not programmable on the workbench, so you have to forfeit a bunch of the I/O pins for external memory. There also aren't a lot of different variations like there are of the common microcontrollers like PICs and AVRs.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

The 6500/1 is not a 6570 or 6571 by any means. But if you like it...

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

I'm guessing the only difference is the 6570 is already programmed. But then I've only skimmed over the datasheet.



Correct. I have a 65134. I tried to use it, to save space, only to determine I could do the same thing in less space with a 6502, 6522, and separate ROM and RAM. The big killer of the '134 in my opinion is the lack of a shift register.

If it's from CSG and it looks like a microcontroller, it very likely does have a 6502 core. Quite recently there was a successful effort to dump the ROM from a 6500/1 using the test mode. See
http://e4aws.silverdr.com/hacks/6500_1/

This was discussed on the cbm-hackers mailing list last year. Someone sent Jim some Amiga keyboard controllers (6570/1), and he was able to extract the ROM from them.

FFFE points to 48, a9, ff, 85, 80, a5, 81, ... which looks like 6502 to me.

It is confirmed - the Amiga keyboard controller is a variant of 6500/1, which in turn is a 6502 based microcontroller. The content's been dumped, reversed, etc.

TAX (maybe?)
LDA #$FF
STA $A580
and I can't remember what $81 is. Possibly STA $__ (zero page)

Thanks everyone, this is very interesting and good to know.

Using http://www.masswerk.at/6502/disassembler.html I get
(Of course the code isn't at 0000)

Seems like an eternity ago... The code should be available somewhere, but I think I still have it here in my archives if not.

Jim

It's in one of the mailing list archives, here: "ROM Dump of Amiga Keyboard controller". Or here.

Great work BTW! Related write up for the 6500/1 firmware of the VC-1520 device.