The history of the Commodore 64 series

When one was sold such an early model, there were some things that could take the C64 offline forever. ;) Things like pulling out cables or module cartridges while the C64 was operating might have been at the cost of some important chips:

- Removing the floppy drive connection would have messed up one of the CIA 6526 i/o chips and the logic IC SN7406.
- Disconnecting the datasette drive might have toasted the MOS 6510 CPU.
- Pulling out a module from the cartdridge slot would have taken out the address manager 906114-01 or the processor.

Later (more mature) versions of the C64 have a newer operating system version (described below) and a 8-pin video out, instead of the old 5-pin connector. Also, the Commodore logo is rainbow-coloured, saying "Commodore 64" from then on and the function keys have become brown.

German fans even call their C64 "Brotkasten", which means as much as "bread box", carefully translated into english... You're right, if you think, that it has something to do with its remarkable form and design, speaking of the first and the C64G model. The latter model is explained later.

The Commodore 64 is driven by the "Commodore Basic 2.0" operating system. It boots into a command line interface, as you (maybe) know it from DOS or Unix. You, as the user, can input simple BASIC code at once. This is an important point, which made and still makes the system more interesting for hobbyists.

There were three different versions of the Commodore Basic 2.0 system. The very first version of the operating system has some severe problems: It causes the system to freeze when the user presses a specific key combination or when displaying certain colours at the same time. However, this errors have been fixed very quickly by Commodore, but the next revision still has errors. For instance, poking into the video RAM, causes the colour RAM to be set incorrectly. This error was fixed in version 3, which is the latest (and probably last official) revision of the operating system. ;-)

You can easily find out your OS version, when entering "POKE 1024,1" at the console. This command addresses the screen memory and should show the letter "A" in the upper left corner of the screen. The first version would display a white "A". Version 2 does not show any letter, although the letter is there. It just has the same colour of the background, which is because of a bug, that occurs while initializing the colour RAM. The third version shows a light blue "A".

The main difference between the two models is the casing. It is similar to the C128 case, smaller and less wide and deep than the old one. The internal keyboard of the C64C is not any different from its predecessor, even as contra-ergonomic as the old one. ;-) All the output/input ports of the C64C are still the same and at their original place. Thus, one could simply connect the old C64 periphery to the new C64C computer, including the power supply. The isolation of the new C64C has improved. The classic model has a pasteboard, surfaced with aluminium, where the C64C has a metal board, which also cools the ICs.

A look into the inside reveals, the mainboard is still the same (Revision C, 1984). The SID, the VIC and the 6526 I/O chips carry new version numbers. The SID 8580 produces a slightly different sound than the older SID 6581. The video chip of the C64C came in two versions: VIC 8562 and 8565; They have another core voltage of 5 V, which is 12 V in the classic C64). What chip version of those two was used, depended on the production date. The voltage converter of the classic C64, that produces really hot temperatures was also replaced by a new model.

Additionally, the C64C was sold together with the operating system "GEOS", developed by "Berkeley Softworks" and stored on floppy disks. In the form of a graphical user interface, already dealing with windows and icons at this early time, it can be controlled by a mouse like most modern operating systems today.

Parts of the C64 community curse the C64C for its different design, because there are some incompatibilities: In fact, there are existing expansions and add-ons that don't work or hardly work with the C64C, because they were produced and set up for a special chip configuration and a bigger case, the C64C does not have. This version also lacks the 9V user port voltage. So, from this time on, expansions have been requiring their own power sources. Yet, the Commodore Basic operating system remains the same: Revision 5, 1983. This, of course, was merely done in the spirit of compatibility. :-)

On the one side, the production costs were decreased, on the other side many expansions don't work anymore, because the 9V user port voltage is also not included, which we already know from the C64C. The software compatibility is nearly 100%, though. The first C64G were sold with a white version of the classic C64 keyboard. Later models have the keyboard design of the C128. The power LED sometimes was green and other times was red, depending on the current inventory of Commodore. Also, the metal Commodore sign was replaced by a cheap foil sticker to save even more money. The production of this model lasted until 1990.

Unfortunately, there is still no reset switch, but you can try typing "SYS 64738". This should reboot your C64. ;-) Or of course, you can get add-ons like the "Final Cartridge", that come with a reset switch and some other useful stuff.

The SX64

The SX64, produced from 1983 to 1986, is a more or less mobile version of the C64 in a big metal case. Its weight is about 11 kg, it came with a 5 inch colour display, an internal floppy drive (compatible to the 1541) and the hardware is to a large extent identically constructed. The grip for carrying the computer can be used as a rack. The keyboard is external, freely movable and conntected via cable.

It has a different welcome message than the classic C64, with other colours, that are better readable on small displays. There is no TV modulator anymore and the datasette routines have been removed from the ROM, although the datasette port is built into the mainboard, however not accessible from the outside. Also, one of the 9V user port pins is grounded, which the original C64 does not have. Commodore had to send out a service pack with an improved ribbon cable for the cartdridge slot, to solve connection problems with expansions. However, C64 modules work.

The DX64

The DX64 is a SX64 with a second floppy drive. But it was unclear, wether it would be introduced to the market or not, because there had been problems with the power supply of the second floppy drive.

The C64GS

The letters "G" and "S" stand for "Game System". It is a somewhat "crippled" C64, without a keyboard and serial port. So, it is a pure game console, designed for the operation of modules. It didn't last long on the market. The production of the C64GS started in 1990 and ended the same year. There were about 80,000 units produced, whereas most of them originated from west Germany, but only 25 % of them were sold. The others were resubmitted to Commodore to be used as spare parts. Also, it was quite a flop. ;-)

The C64 - Golden Edition

In 1986, Commodore had sold 1.000.000 C64 computers and to celebrate this jubilee, 200 C64 Golden Edition computers (with a golden case) were given away to popular people that helped developing the C64 and supported it.

They were not sold officially and it is proven, that there were more than 200 exemplars: Officially, serial numbers from 1.000.000 to 1.000.199 belong to the golden edition, but there have been higher serial numbers on golden C64 computers. It is said, that there are up to 1000 golden C64 around. Unfortunately, one cannot easily afford such a C64. ;-)

The Educator 64

This version of the C64 has the case of a PET. It was sold to schools for educational purposes. The cause of this might have been, that the bigger case is more difficult to steal. ;-)

The ALDI C64

ALDI is the popular name of a german supermarket company, that sold C64 computers in 1986. Those lack the 9V user port voltage and are therefore not very compatible to many expansions. Significant is the beige case of the classic C64 and the bright keyboard like the C64C and the C64G. Its "Commodore" sign is also made of foil. This model was only sold in germany, although it is "Made in usa" according to its inscription.

So, you want to try and experience your newly gained knowledge, brought to you by this tutorial, but you don't want to spend any money for an expensive nth-hand C64 from "www.ebay.com"? If so, don't click on the link and read on. ;-)

To your left, you see a screenshot of the VICE (Versatile Commodore Emulator), which is capable of emulating a Commodore 64 computer on todays "stayed off the art" machines. ;-) The screenshot has been taken under Windows, but the emulator is also available for other architectures and real operating systems, such as Unix, DOS, IBM OS/2, Acorn RISC OS or BeOS.

The emulator allows a detailled configuration of video, audio, input, output and controlling devices, such as VIC, SID, floppy drives, datasette drives or joysticks. It is capable of opening disk and datasette images, as well as recording datasette images and much more. Of course, it is also able to emulate C64 games. ;-)

You can download it from the VICE homepage.