Commodore plus/4

Resources

Wiki
C64 Wiki
Plus4World – pretty much everything you need
Carlsen Electronics – plenty of materials
Zimmers.net – documentation, schematics

Documents

No documents found.

Internals

Power Supply

The square power socket has the pinout as on the following diagram:

It is possible to use a regular C64 power supply with Plus/4. After cutting off the original plug there should be four cables:

two black wires are 9V AC
brown is +5V DC
blue is DC GND

Because it is pretty difficult to find a square DIN plug today, it is possible to make a replacement one by cutting unnecessary pins in a DIN-8 plug (non horseshoe version) so the remaining pins form a square. Because there will be no shield, a special caution has to be made to connect the plug always in the correct orientation, with the black AC cables on the top.

Keyboard

Motherboard

The infamous MOS 7360 TED sits in a separate housing chamber with a radiator attached through a heat-conducting paste. That is probably why Plus/4 machines are good donors of TED chips to C16 and C116, where these chips fail miserably.