August 1982, the world gets to buy the C64
January 1982 is a date that’s written in bold in computing history books as it was then that the C64 was first shown to the world at the Vegas CES. With all the buzz about this new awesome machine that Commodore was going to release, and this was just shortly after the success of the VIC-20, Jack Tramiel pushed to get these machines out on the market as soon as possible.
It was envisaged to have enough machines ready for a release in April. This of course was again, just as with the deadlines set for the prototypes at the Vegas CES, something that was close to impossible to realize. Nonetheless, Jack kept pushing his team to the limits and eventually they managed to get everything done so sales could start in August, exactly 30 years ago today.
In this article, I’ll look back at some of the challenges the team at Commodore faced during these nerve-racking months that led to the June CES, just 6 months after the unveiling of the prototypes as well as some of the things we took “as is” on the C64 but which could have been quite different if only the engineers would have had more time or if Commodore would have allowed for a slight increase in production cost.
The first challenge that was put before the engineering team (which had at best only 15 engineers) and consisting of amongst others Charles Winterble, Robert Russell and Al Charpentier was the choice for the OS. They had initially used BASIC 2.0 for the prototypes, the then already quite antiquated operating system that was used in the PET and talks were ongoing on the popularity and use of CP/M, so it was only logical that this was a serious candidate. It was a high-level operating system and it would lock-in an existing CP/M user base for the C64. The problem was that the requirements for this OS would have meant a serious redesign of the system ROMs and as time was of the essence, the whole CP/M discussion was moved and settled: Commodore would produce a separate CP/M cartridge based on the Z80 processor (a processor that would be integrated a couple of years later in the C128).
Commodore did have the more powerful BASIC 4.0 on the shelf (as it was going in its P and B line of computers), but memory limitations meant that this was a no-go for the below $600 computer.
So if you’re wondering why you had to use complex entries to write to for instance your disk drive, or had to PEEK and POKE to get those graphics going, you can blame it on those design decisions.
The next obstacle was that of “backward compatibility”. With the sales of the VIC-20 topping every chart, it was logical to make the new machine capable of running the VIC’s software and using its peripherals.
Running the VIC-20 software however, would have meant yet another redesign of a chip, this time the VIC-II graphics chip as it was not capable of displaying the old VIC-I resolutions. Given the stated deadlines, this idea was scrapped. Commodore however called the C64 “limited” backward compatible, as simple programs that did not use POKEs and PEEKs could technically run on both systems.
There’s a famous Jack quote on this topic, when Jack had his say on the whole compatibility discussion: “Don’t worry about compatibility. We’ll sell them a new computer for cheap, so who cares about compatibility”.
With the VIC-II chip giving the computer its full color experience Al Charpentier wanted to make it as good as physically possible. To achieve this, he made a risky last minute change to the chip (it involved separating the clock generators on the chip to prevent a blurring effect caused by interference of the black and white and color signal). As a result, the white characters on dark blue screen (which was chosen for the prototypes) didn’t look good anymore, so they had to make it light blue on dark blue (and hence, the “classic” C64 screen, that most of us will remember, was born out of a last-minute “bad” design decision).
This wasn’t the only issue with the new graphics chip. It also seemed to cause light blue sparkles on a dark blue background when it heated up, something which became known as the “sparkle bug”. It was fixed in the software (basically turning the sparkles into dark blue, so it wouldn’t be visible anymore).
Nonetheless, given all these challenges (and there were many more), the team had everything ready for the June CES show, where Commodore could finally show the world the finished C64s and not just prototypes.
The assembly lines picked up the pace and started producing VIC-II, SID chips, circuit boards and all the needed parts in large quantities, ready for selling the revolution to the world, which they did 2 months later in August 1982, now 30 years ago.