Apple 1 clone made with AVR parts

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Hi all,

have made an Apple 1 Clone using a MEGA32 for Video
and a ATtiny2313 for the PS2 Keyboardcontroller.

Have fun
Franz

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I think you forgot to give the URL?

http://www.achatz.nl

RES

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Wow, this is so cool! Excelent, congratulations Franz!

The Dark Boxes are coming.

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Thanks, guys :-)

Here a foto showing a running A-ONE machine

Franz

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Initially I thought that AVR was also emulating the 6502. Question: are 6502's still so widely available? And I think one could pull a project of the sort, putting the entire A-One, or whichever is their favourite, into a single FPGA. I think I've seen some projects like that. Any plans for doing that in near future?

The Dark Boxes are coming.

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I have seen a project making an Apple II just with a FPGA.
But i did the Apple 1 because Steve Wozniak allowed me using
his Apple 1 WOZ Monitor for this project.
The 6502 CPU and 6821 PIA are still available :-)
I think, the Apple 1 part can be done using a single ATMEGA128
and 32KB external RAM.

Franz

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I see. Being able to use the original monitor with personal courtesy of Woz is of course a great motivational factor.

Let me know if you're up to recreate some LSI-11 based stuff. Many soviet comuters were based on that architecture, I have one that's assumed to be "the first russian home computer", it has LSI-11 clone beating inside. And in fact the CPU is still available, too. Eats 80mA at 5V!

The Dark Boxes are coming.

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I can remember the PDP-11 (LSI-11).
A very nice big machine.
Was allowed playing with one of this machines in 1979.
This was great fun, used a teletypewriter on it :-)

Franz

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Nice project, it definitely gives you bragging rights. You might want to move it or repost it to the "Post Photos of your AVR Project .." thread in the Off-Topic forum.

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Thats a good idea.
By the way, there will be a great Assembler available for the A-ONE.
San Bergmans, the designer of the SB-Assembler, is doing this part.
Link to his Apple 1 project: http://www.xs4all.nl/~sbp/projec...
There are a lot of technical Apple 1 background infos at his page.

Franz

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Maybe this is interresting :-)

http://instruct1.cit.cornell.edu...

/Bingo

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Quote:
Maybe this is interresting

http://instruct1.cit.cornell.edu... ... 3/website/


The problem with this project is that it does not run at the speed and timing of the 6502.
I have a preliminary design that I believe will run at the proper speed and timing.
One of these days I'll get back to it.

Regards,
Steve A.

The Board helps those that help themselves.

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Wow, I clicked the ATTINY site and was instantaneously overstimulated. I would have to click off about half of the clutter to start digesting what was offered there. A very artistic, well done site. However, when I am in an AVR state of mind I need things to be more focused. Sorry.

Just some guy

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did somebody trie it out emulating a 6502, yet?

Franz

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That is awsome!


My AVR Site

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Quote:
did somebody trie it out emulating a 6502, yet?

As I said above, I have a design, but I haven't implemented it yet. Maybe I'll dig it out and try it this weekend.

Regards,
Steve A.

The Board helps those that help themselves.

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Hallo Svofski,
do you have a block-diagram or schematics
from the LSI-11 or the PDP-11.
This will be my next project.
Franz

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I did start back on my 6502 emulation last weekend. I got pretty far through it (maybe 25% of the opcodes). It is a little harder than I thought that it would be. The V flag is handled differently between the AVR and 6502 in many of the functions. So I've been having to use up a couple of cycles to correct that, making things tight. I'm trying to do it with the AVR at 14MHz to match the Apple II base frequency. If you do it at 16MHz it would give you two more clocks and ease things up. Also I am trying to get as close to the original timing of all the address and signal lines. I could drop the "sync" line and save a couple more clocks per opcode.

Regards,
Steve A.

The Board helps those that help themselves.

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franzachatz wrote:
Hallo Svofski,
do you have a block-diagram or schematics
from the LSI-11 or the PDP-11.
This will be my next project.
Franz

Wow Franz, that's a quick decision ;)
No, I don't have schematics. I have some reference docs for equivalent Russian CPU, but I don't know if they're sufficient to make a hardware emulator.

This is a project that emulates PDP-11 in an FPGA. The site is not answering right now, I'm not sure if it ever will, but here's a google cache link:
http://64.233.161.104/search?q=c...
I think it could be retrieved via archive.org in case of emergency. I'll keep looking for more data meanwhile.

The Dark Boxes are coming.

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Franz,

I used to have binders full of PDP-11 stuff. Maybe I can find some schematics or block diagrams.

Randy

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Who, i found this project, yesterday:
http://www.sparetimegizmos.com/H...
Its a PDP 8 clone, and very nice made.
I'll keep looking and after i finished the CAS-Interface
for the A-ONE the new project starts.

Franz

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This place has some PDP-11 manuals, but they are not very comprehensive:
http://pdp-11.org.ru/info.html (the site is Russian but manuals are English).

This site (amazingly, it's being run on an LSI-11 with 2mb of RAM), has links to PDP-11 software archive, some documentation and emulator(s). I hope this may help.

The Dark Boxes are coming.

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I could not find anything connected with RT-11 on that site. Were there no RT-11 hackers in Russia?

- John

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Hallo svofski,

do you have a name?
My name is Franz, comming from Holland, i am a German (from Bavaria) and maybe we can talk via mail.
If you are interessted then let me know at:
franz@achatz.nl

Franz

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@jfiresto: actually RT-11 was probably much more widespread here, but it's mostly associated with smaller, almost personal, LSI-11 based computers (if you're into Soviet computers, you could be familiar with DVK series). That site, as it seems, belongs to hardcore PDP-11 fans who see RSX-11M as the ultimate OS for their favourite platform. I remember I could find images of both RSX-11M and RT-11.. Not sure about their legal status though. For me, a few minutes of brain scratching over long forgotten stuff were more than enough ;)

@Franz: you've got mail

The Dark Boxes are coming.

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the A-ONE manual is ready and online.
Look at: http://www.achatz.nl

Franz

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Good project OP! Have you looked into any of the apple emulators? They may have source code that might help with understanding the archetecture.

LSI-11: I played around with one years ago. the LSI-11 was encorporated into a VT100 terminal. Nice little industrial toy.

DFR