Click on the advertisement to see a larger picture.
The Proton Compact Computers were developed and sold by the dutch company Proton, based in Naarden, around 1983. The concept of the PC-2 model is a modular design. As you can see in the (dutch) advertisement one could start with a case with keyboard and power supply, add a cpu card with ram and rom, a videocard or a small character display, a cassette interface or a floppy disc system with a Proton developed operating system. The system was available in kit or as assembled machine.
The specifications of the cpu
- 6502 at 1 MHz
- VIA 6522
- 6K monitor in EPROM
- 10K Basic in EPROM
- 2 sockets for 16K EPROM or RAM
The graphical videocard delivered a 578x229 or 25 lines with 80 characters display and a fast 10kB/minute cassette interface. An alternative lowercost 16 character alphanumeric display (see the pictures below) was available. Also the casstte interface was available as low cost board.
For more expansion a 64K dynamic RAM card with an ACIA and Centronics printerport was available. A floppy disk controller for a maximum of 4 5 1/4 flopy drives, giving 400K capacity per drive, with a DOS was available.
In the next prictures you can see the two Proton systems I ahev in my collection. Both have the alphanumeric display. One has the low cost cassette interface. On that one the previous owner has broght one of the EPROM/RAM sockets to the right top of the keyboard, presumably for faster experiments.
Alas I have no further documentation on this nice looking system.
Note the socket on the right,
it is one of the EPROM/RAM sockets extended.
The display shows the default prompt of the monitor.
The basic Proton system: just the cpu board
Here the small cassette interface is added and the flatcable can be seen extending the EPROM/RAM socket to the outside.
Both Proton machines come with the original suitcase with on top the stylish Proton brand.
The alphanumeric display is very good readable!