Questions tagged [commodore]
Commodore Business Machines and their products. Use more specific tags like [commodore-64] or [amiga] instead if appropriate.
130 questions
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Help understanding the Commodore 64 cartridge memory use and lifecycle
I've recently become interested in creating my first C64 cartridge to host a small app I've been fooling around with. I've done some preliminary research and discovered the size (8k or 16) and memory ...
- 11k
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Can CBM DOS truncate REL files?
I know that I can make a REL file bigger, by writing to a record after the end of the file --- the file gets automatically extended to include that record.
Is it possible to also make files shorter ---...
- 1,546
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What might cause my Commodore 1541 and FSD-1 disk drives to have a bus conflict
I'm seeing some strange behavior on my Commodore 1541 and FSD-1 disk drives. Both drives seemingly work fine when attached to the C64 by themselves, but if I set the FSD-1 to be device 9,10 or 11 - ...
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Reduced Circuit C64 Clock Generator newer motherboard Y1 frequency question
The C64B, C, and E motherboard’s 250425, 250466, and 250469 all have the reduced oscillator circuitry when the Y1 crystal is connected directly to the 8701 Clock Generator. This clock generator has an ...
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How to detect if the KERNAL load/save routine is currently active on a CBM system?
On a Commodore 64, I have a custom interrupt routine running in parallel with a main program, and I need to detect if the KERNAL is currently performing a LOAD or SAVE operation via I/O. Unfortunately,...
- 4,681
3
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Amiga Forever fullscreen mode is display on second monitor instead of first monitor [closed]
I'm using Amiga Forever on Windows 11 with two monitors.
Now I have a recent new problem with the fullscreen mode in Amiga Forever (It used to work correctly).
If the Amiga Forever program is on ...
- 458
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Unix tools for manipulating Commodore CP/M disk images
I'm looking for some (command-line) tools that can transfer host files on a Unix or Linux machine to and from Commodore .D64, .D71 and similar image files in CP/M format. The particular use case I ...
- 29.5k
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How are the unused bits within the Commodore 1541 DOS filetype byte handled?
I am curious to learn more about how the original Commodore 1541 DOS handles the filetype byte. This byte is the first byte for every directory entry on disk, and is not only interpreted as the ...
- 11k
5
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2
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Amiga 500 left mouse button is not working. How to diagnose and fix it?
I've recently bought a Amiga 500 (A6 board). This Amiga works perfectly and starts as it should, except for the fact that when I hover on a icon and click my left mouse button to open it, it doesn't ...
- 113
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How to interface with W65C51 UART
I want to build my own computer with retro-ic's. One of those ic's that I want to use is the W65C51 from Western Design Center. I am trying to connect it to a Arduino to learn how to interface with ...
- 113
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Commodore 128 bottom row of keys work with different shift keys
I have been playing with a Commodore 128 that I picked up but I have noticed one, what I would call, weird keyboard problem(?).
If I scan on the bottom row of the keyboard every other key works with a ...
- 73
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Why didn't Commodore run the 6502 at 2 MHz? [closed]
The Atari 800, in 1979, ran the 6502 at 1.79 MHz. That rounds to 2, and was presumably a 6502A rated for 2 MHz, underclocked.
Why did Commodore keep running their 6502 computers at 1 MHz, even the 64 ...
- 65.3k
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Why was the 1540 a computer in its own right?
The Commodore 1540 disk drive, along with its better-known successor the 1541, is a computer in its own right, with its own 6502 CPU.
Why was it designed like that?
It adds significant cost to the ...
- 65.3k
9
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The works of Frontier Manufacturing
Having spent the last however many decades believing Commodore Semiconductor Group was a simple rename of MOS Technology, I just watched a video – quite interesting in its own right – which casually ...
- 65.3k
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What process node enabled the 6502 to reach 2 MHz? [duplicate]
The original version of the 6502 was rated for 1 MHz, but before the end of the decade, the CPU was available in a 2 MHz version. Presumably what changed was Dennard scaling: make the transistors ...
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