239
votes
Accepted
How did Commodore's anti-Microsoft Easter Egg work?
I'm the author of the TPUG article.
The "BILL GATES SUCKS" message isn't really an Easter egg; that was just a conceit of mine to make the article a bit more interesting and to turn it into a bit of ...
- 7,023
74
votes
Did computer games for Commodore 64 really take "25 minutes" to load "if everything went alright"?
Theoretically it could take 25 minutes (or more), in practice it never did.
Theoretically it could, because the C-64's built-in tape handling routines had a data rate of about 300 bit/s. That's 37.5 ...
- 9,820
65
votes
Accepted
Why did Commodore fill their power supplies with epoxy?
Epoxy offers two advantages -- it is an electrical insulator, and it conducts heat better than air. Transformers and inductors are generally potted with epoxy for this reason. [ref] Perhaps the cause ...
- 8,663
64
votes
Accepted
Why are C64 games inconsistent with which joystick port they use?
As Wilson points out in his answer, it has to do with how the CIA chips interact with the keyboard and the joystick ports, and the confusion that can arise trying to determine where input is being ...
- 9,795
63
votes
How did Commodore's anti-Microsoft Easter Egg work?
That's not a real easter egg. Someone just made an effort to find random seeds that produce the numbers to create the intended words. It would be an easter egg if the seed numbers were in some way ...
- 3,804
62
votes
Why did the VIC-20 and C64 have only 22 and 40 columns when the earlier PET had 80 column text?
One reason was likely that the VIC-20 and C64 did not have their own displays, but were designed to be connected to a television set. The interface between the computer and the television was not ...
- 6,849
60
votes
Accepted
Why do programmable sound generators like SID include a noise generator?
One basic distinction in acoustics is the one between sounds that oscillate with a pattern that is repeated over time and sounds that are chaotic in nature, and show no repetitive pattern.
Sounds ...
- 925
53
votes
How did C64 games handle music during gameplay?
Your assumptions about timing and interrupts are correct. Actually, it is surprisingly easy to add SID music to games because they tend to follow a basic pattern.
Compose the tune in a C64 SID editor....
- 60.1k
52
votes
Accepted
Why did Commodore 64 cartridge games disappear?
Time to market was another factor. I worked in the games industry in the 1980s and when we were getting the final game from the developer, mastering to cassette and disk took just hours before they ...
- 536
49
votes
Accepted
Why did the C64 have ← and ↑ as dedicated keys?
The ← and ↑ symbols were originally included in ASCII-1963 as programming operators. They were used in a number of programming languages at the time, but the only common usage left today is in ...
- 4,517
48
votes
Why did the VIC-II and SID use 6 µm technology in the era of 3 µm and 1.5 µm?
After some more research, I believe I've stumbled across the real answer: The VIC-II and SID used a larger process node size because Commodore's fabrication line circa 1981 was uniquely positioned ...
- 719
42
votes
Accepted
How can I store a machine language program to disk on a C64?
I have looked all around online, but I cannot find on how to do this.
Well, you won't, as the C64's BASIC2 does not provide such function or a monitor. The old PETs had TIM in ROM, while BASIC 3.5 ...
- 213k
41
votes
Accepted
Why do all the Speech Synthesizers have that same Voice?
The ones you list are all S.A.M, from what is now SoftVoice Inc. It was developed first for the Apple II, Lisa, Atari 8-bit machines and the Commodore 64; based on awareness of those versions, the ...
- 35.9k
39
votes
Accepted
C64 BASIC: How to suppress the '?' sign when using the INPUT command?
Use the INPUT# command.
The INPUT# command is meant for non-interactive I/O on files or devices, i.e. reading from a file on disk, serial port, whatever. Because it is non-interactive, it will not ...
38
votes
Accepted
Commodore 64 to modern TV
The VIC-II chip inside the C64 computer outputs a S-Video signal, which is mixed and modulated into the matal box that contains the UHF modulator circuit. Earlier models made composite video available ...
- 18.6k
37
votes
Why did Commodore 64 cartridge games disappear?
A cartridge was limited to 16 kbytes ROM, and some were only 8k. There would be plenty of RAM to use, but the code and data must fit into the 16 kbytes. As programs became more sophisticated, the ...
- 8,663
36
votes
Accepted
How can I overclock my Commodore 64?
The basic principle behind overclocking is that if you speed up a clock, everything that runs from that clock will go faster. But there are some parts of your computer that you don't want to speed up,...
- 11.4k
36
votes
What was the purpose and history of the C64's special keys?
The Restore key triggered the NMI (non-maskable interrupt) line; to actually have an effect it had to be combined with Run/Stop - it would soft-reset the machine (via an indirect jump vector that ...
- 1,593
35
votes
Accepted
C64: Why is POS(π) faster than POS(0)?
That interpreter apparently parses the source text, or at least the numerical literal values, at every execution. π is a single-byte magic token, therefore, as soon as it is recognized, it is ...
- 18.3k
35
votes
Accepted
What is the Commodore 64C "France version" and why does it need a beefy resistor?
As noted in the question, the resistor is there to allow something to consume more current without voltage dropping too much.
But what consumes more current may not visible in the schematics.
France (...
- 28.3k
34
votes
What's the deal with Commodore's RESTORE key?
TL;DR:
There is no fundamental difference just because a different interrupt is used. For all practical purpose the Restore-key works like the Apple II's Reset-key or the PC's Ctrl-Alt-Del key ...
- 213k
33
votes
Accepted
Why does the Commodore 64 have 4K of non-banked RAM at $C000?
I wonder why the Commodore 64 memory map was created as it was.
As so often it helps to look at a machine's predecessor; in the case of the C64 that's not the VIC 20, but the Max Machine, a very ...
- 213k
31
votes
Accepted
Install Commodore 64 on VirtualBox
It's not possible. VirtualBox only supports emulating IBM-compatible x86 and x86-64 systems. The Commodore 64 uses a 6510 CPU and a wildly different architecture.
In order to run Commodore 64 ...
- 8,550
31
votes
Why did the VIC-20 and C64 have only 22 and 40 columns when the earlier PET had 80 column text?
Use of TV as monitor is the reason for these low resolutions.
The issue is that the color resolution of TV is very low. While B&W TV could resolve pixel small enough for ~400 to ~600 pixels, color ...
- 3,649
29
votes
Accepted
What are the differences between a PAL and NTSC C64?
Hardware-wise, the Commodore 64, like most early computers, was synchronized to its graphics output: in the case of the C64, the CPU clock was derived from the timing crystal in the video hardware.
...
- 8,550
29
votes
Accepted
How did the "rub joystick port to continue" in the Creatures 2 infinite lives cheat work?
Originally intended for use with paddle input devices (and, like everything else on the C64, since exploited to the limit), the C64 has A/D converters readable from code exposed on the joystick ports. ...
- 4,486
29
votes
Why does the C64's LIST command choke on REM statements with a Shift+L?
Internally, a BASIC program isn't represented as the text you see when you list it, but as a tokenized data structure where each of the language keywords are represented in an optimized 1-character ...
- 4,486
29
votes
Accepted
How to use BASIC after "LOAD "$",8 on the C64
Try using the "new" command. This clears BASIC's memory, so that you can write a new program.
- 11.4k
29
votes
How to detect a real Commodore 64, THEC64, or VICE emulator in software?
In general, no there is no reliable way to detect an emulator (if it's any good). Especially if it's actively developed.
The trick that worked yesterday probably don't tomorrow as emulation improves. ...
- 4,486
28
votes
Accepted
Dumping and archiving C64 disks
The simplest method of archiving old C-64 disks would be to get a ZoomFloppy and a 1571 floppy drive from eBay. I say 1571 because it's much less likely to have alignment problems.
The ZoomFloppy ...
- 396
Only top scored, non community-wiki answers of a minimum length are eligible