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For quesitons regarding the products of Commodore Business Machines.

6
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4answers
366 views

Early Basic memory management

Can anyone verify or correct my memory here? Long ago, I had access to a Commodore PET which I think had 8kB of memory. Also slightly less long ago, I had a Commodore 64 with its "elephatine" 64kB. ...
1
vote
2answers
219 views

Commodore Amiga 600 Software Failure. “Error: 8000 0004 Task: 000026D0”

Software Failure on Commodore Amiga 600 when I insert a floppy in drive. Software Failure. Press left mouse button to continue. Error: 8000 0004 Task: 000026D0 Independent from the floppy I ...
6
votes
2answers
620 views

Is it possible to bank out Kernal in Commodore PET, VIC-20 or 264 series computers?

You can bank out Kernal ROM in C64 using $01 register. This was preferred by game/demo coders who wants to employ self tuned routines and wants to expose ram 'underneath'. You can do lda #$35 : sta $...
7
votes
2answers
461 views

Were external floppy drives for Atari ST and Amiga inter-compatible?

Were external floppy drives for Atari ST and Amiga inter-compatible? For example, Commodore 1541* had its own serial bus protocol. But what about the external 3.5" DD floppy disk drive on 23pins D-...
8
votes
3answers
830 views

How to spin up 1541 drive without C64

I have a 1541 drive and I want to make it spin but I don’t have a Commodore computer. I don’t need to read data, I would just like the drive to spin. Can I manually tell it to spin using a raspberry ...
6
votes
4answers
488 views

What was the 2nd best selling computer ever? [closed]

It's widely known that the Commodore 64 was the best-selling single model of personal computer. Which computer make & model got second place? To clarify, I'm looking for an objective answer about ...
5
votes
2answers
353 views

Why did Commodore files not include metadata to say where in memory to load it?

On the Commodore 64, (and I believe also the VIC-20, PETs etc.) you may instruct BASIC to LOAD "something",8 to load a file to the start of BASIC's area (and that address may vary between machines),...
3
votes
2answers
163 views

Commodore VIC-20/64/128/16/Plus 4 floppy disk drive replacement

We all know that floppy disks are getting hard to find, and floppy drives are fragile to begin with (especially Commodore's 1541 drive). I know that several companies and parties have released floppy ...
5
votes
2answers
332 views

Getting your Commodore VIC-20, 64 or 128 online

Back in the day, of course we used modems ("dial-up modems" in today's parlance) to get our Commodores connected to other systems. These days I know several people have concocted options to get ...
0
votes
1answer
231 views

Amiga 500+ does not start up [closed]

Amiga 500+ does not start up. It has been offline for a considerable amount of time. The machine powers up but does not move from that point. I have inserted the workbench disk. Can anyone advise the ...
1
vote
1answer
318 views

Amiga versus Atari ST computer introductions [closed]

I'm interested in the time, place and manner in which some historically important computers were introduced to the world. For example, the Macintosh was presented in January 1984 by Steve Jobs, first ...
5
votes
7answers
815 views

Benchmark between Home computers? What can be a valid parameter for that?

I'm writing my thesis about the home computer market between 1977 and 1984 (focusing on Commodore Inc.so PET, VIC-20 and 64 and competitors). I'm trying to plot a curve describing the technological ...
23
votes
3answers
3k views

Why did Commodore sell CPUs to its competitors?

Many of the most popular personal computers and video game consoles of the 1970s and 1980s, including those made by Commodore, Apple, and Atari, used the 6502 CPU (or some close relative, such as the ...
12
votes
1answer
363 views

Where are the blueprints of MOS chips?

Atari historians have been able to find documents and tapes of chips and hardware developed at Atari. E.g. http://atariage.com/forums/topic/154479-new-gtia-chips/ . Nothing like this is happening ...
8
votes
1answer
574 views

What is this extra lead in my monitor cable?

I have a breadbox Commodore 64 with a Commodore 1702 monitor. My monitor has three RCA-style inputs on the back: Audio (White) Luma (Yellow) Chroma (Red) I purchased a cable which claims to be an ...
46
votes
2answers
9k views

Why did Commodore fill their power supplies with epoxy?

If you know anything about the Commodore 64 (and other Commodores, really) you know that Commodore really went the cheap route and produced some awful power supplies. The Commodore 128 PSU isn't ...
93
votes
2answers
16k views

How did Commodore's anti-Microsoft Easter Egg work?

A couple years ago the Toronto PET Users Group published an article (The Great Commodore/Microsoft Easter Egg War, on p. 7) about a newly discovered anti-Microsoft Easter Egg that Commodore hid in the ...
8
votes
1answer
639 views

What is the difference between the Commodore 1701 and the 1702?

Among the monitors offered by Commodore were the 1701 and the 1702, which, to my recollection, looked pretty much identical. Were there any cosmetic, functional, or other differences between the two?
12
votes
1answer
317 views

What is the proper way to test the PSU output for a Commodore 128D?

This question is directly related to comments on the more general question and answer here. The Commodore 128D and 128D-CR have an internal PSU that can be readily and safely disconnected from the ...
34
votes
1answer
2k views

What precautions to take when powering on old computer for the first time in years

I have a Commodore 128D that hasn't been powered in about 15 years. I want to begin using it again. It has been stored in cool dry places like attached garages, in a cardboard box. I hope this ...
6
votes
1answer
399 views

Is there a device that will take composite video from a vintage computer and filter it so it is green or amber like the old monochrome monitors?

I know some monitors have a mono/green switch, but I'd like to do this with my 1702. If one doesn't exist, I'll probably try and make one (somehow).
23
votes
3answers
2k views

Why does the Commodore C128 perform poorly when running CP/M?

I have seen several claims of poor performance of the C128 when running CP/M, and would like to better understand these claims, especially in comparison to other CP/M machines of the early to mid-...
9
votes
1answer
235 views

Selling computers via dealers and the mass market

As discussed in Origin of dealer networks, the two main ways to sell computers are, and particularly were in the old days, Three digit price tag sold to individuals => mass market, department stores ...