A brief history of the C64
The C64 was introduced to the USA home computer market in September 1982, and sold about 17 million times wordwide, with up to three million sold in Germany alone. This number exceeded Commodore's predecessor, the Commodore VIC-20 (aka: VC-20) and therefore has always been a financial backbone for Commodore, during its time period. Because the C64 was so successful, a large software industry grew up to support it. In its time, there were more than six thousand programs which ran on the C64, with new ones being written every day, and this huge
existing software base has played a major part in the evolution of the system's successor, Commodore 128.
The C64's 6510 CPU had been developed by MOS Technologies and was compatible to the 6502 CPU. The main difference between the two CPUs was that the 6510 had a real I/O port, while the 6502 does not. The software, which made up the C64's operating system, was stored in 3 ROM chips, and contained the Commodore Basic 2.0 (discussed later in this article), along with the character set, and the kernal. Because the C64 had a memory address of 64KB (although data from the ROM chips use 20KB of this RAM), the CPU took full advantage of the 64KB (which, by the way, was the reason why the C64 was named) by disabling the ROM chips.
Connecting the C1541 external floppy disk drive, you could load games or data from 170KB single sided 5.25” SD (single density) disks using its own disk format. Although DD (double density) disks also worked, HD (high density) disks wouldn't. The more old-skoll way of gaming was to use the C1530 datasette recorder. This was capable of not only storing and recalling computer software on ordinary cassette tapes, but also pre-recording programs you have purchased. The C64 lacked a hard drive, and so installing and running programs on them for faster access was not possible. The serial port at the back of the C64 handled printers and other peripheral devices.
The design was basically the same as the VIC-20 design: Black keys and orange function keys (from F1-F8), and it was said that a few computers have the more angular keys of its predecessor. Earlier models even had some differences, such as the 5-pin video out. Furthermore, the text located next to the power LED said “C64” instead of “Power”, and the caption in the upper left corner said “Commodore”. These models were unstable and unreliable, and were sent back by customers. Most of these models were defective after one week of operation, but Commodore exchanged them quickly.
When an early model was sold to a customer, there were some things that the user did that could take the C64 offline forever. Removing the floppy drive connection, for instance, would have messed up one of the CIA 6526 I/O chips, as well as the logic IC SN7406. Furthermore, disconnecting the datasette might have toasted the MOS 6510 CPU. Also, pulling out a module from the cartridge slot would have taken out the address manager 906114-01 or the processor.
Later C64 models had a newer operating system, along with a 8-pin video out, instead of the old 5-pin connector. The Commodore logo was also rainbow colored and the function keys became brown. German fans even called their C64 “Brotkasten” (translation: “bread box”), due to its remarkable form and design, in relation to the first and C64G model.
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