Commodore 64 and Amiga Connector Pinouts

This page provides a quick reference to some of the most commonly used connectors found on the Commodore 64 and classic Commodore Amiga computers.

Warning: Always verify connector orientation and pin numbering before connecting any hardware. When working with power supplies, measure the actual voltages with a multimeter before connecting the PSU to the computer.

Commodore 64

The Commodore 64 uses several different connectors for power, video, joysticks, serial peripherals, the Datasette, the User Port and expansion cartridges.

Power Connector

The Commodore 64 uses a dedicated power connector providing two voltage rails:

+5V DC
9V AC

The 5V DC rail is particularly important because an incorrect or excessive voltage can damage components on the C64 motherboard.

Before connecting an original or replacement PSU, it is strongly recommended to measure the output voltages with a multimeter.

Commodore 64 power connector pinout

Important: Never rely solely on cable colours when identifying power connections. Always verify the actual voltage and polarity with a multimeter.

A/V Connector

The Commodore 64 uses an 8-pin DIN connector for audio and video output.

Depending on the cable and display device, the connector can provide:

Composite video
Luma
Chroma
Audio
Ground

Commodore 64 A/V connector pinout

The exact signal configuration depends on the cable being used and the video input required by the display.

Joystick Ports

The Commodore 64 has two joystick ports using 9-pin connectors.

The ports support standard digital joysticks with:

Up
Down
Left
Right
Fire button

Commodore 64 joystick port pinout

Joystick Port 1

Joystick Port 1 is connected to CIA 1 Port B.

Joystick Port 2

Joystick Port 2 is connected to CIA 1 Port A.

The joystick interface can also be used for custom hardware projects and other digital I/O applications.

Serial Port

The C64 serial port is used to connect peripherals such as:

Commodore 1541 disk drive
Commodore 1571 disk drive
Commodore 1581 disk drive
Commodore printers

Commodore 64 serial port pinout

The serial interface uses Commodore's proprietary serial bus protocol.

Datasette Connector

The Datasette connector is used to connect Commodore cassette tape drives such as:

Commodore 1530 Datasette
Commodore 1531 Datasette

Commodore 64 Datasette connector pinout

The connector carries the signals required for cassette data communication, motor control and power.

User Port

The Commodore 64 User Port provides direct access to I/O lines from CIA 2.

Commodore 64 User Port pinout

The User Port can be used for:

Custom electronics
Digital I/O
Serial interfaces
Modems
Printers
Hardware experiments

The User Port is particularly useful for retro-computing hardware projects because it provides direct access to the computer's I/O subsystem.

Expansion Port

The Commodore 64 expansion port allows external hardware to communicate directly with the computer.

Commodore 64 expansion port pinout

Common uses include:

Game cartridges
Memory expansions
Diagnostic cartridges
Fast loaders
Modern cartridge interfaces

The expansion port provides access to the system bus and is widely used by modern C64 hardware projects.

Amiga

Classic Commodore Amiga computers use several different connectors depending on the model.

This section focuses primarily on the external power supply connector commonly used by systems such as:

Amiga 500
Amiga 500+
Amiga 600
Amiga 1200

Amiga Power Supply Connector

The classic external Amiga power supply provides three main voltage rails:

+5V
+12V
-12V

The commonly reported cable colours are:

Cable Colour	Function
Black	GND / Ground
Brown	+12V
White	-12V
Red	+5V
Yellow	Shield

Amiga PSU connector pinout and cable colours

Important: Cable colours may differ between power supplies and replacement cables. Always verify the actual voltage and polarity with a multimeter before connecting the PSU to your Amiga.

Original Amiga Power Supply Output

Different Amiga models and PSU revisions were supplied with different current capabilities.

PSU Type	Part Number	+5V	+12V	-12V	Combined Power
A500 Type 1	312503-02	2.5A	1.0A	0.1A	25.7W
A500 Type 2	312503-03	4.5A	1.0A	0.1A	35.7W
A600 / A1200	391029-02	3.0A	0.5A	0.1A	22.2W
A600 / A1200	391029-03	3.0A	0.5A	0.1A	22.2W

Amiga original PSU output specifications

When replacing an original PSU, make sure the replacement provides:

The correct voltage levels.
Correct polarity.
Sufficient current capacity.
The correct connector and pinout.
Proper grounding and shielding.

Safety

Vintage power supplies should be treated with caution.

Before connecting a PSU to a Commodore or Amiga computer:

Inspect the PSU for visible damage.
Check the power cable and connector.
Verify the connector pinout.
Measure all output voltages with a multimeter.
Confirm the polarity of every voltage rail.
Check for shorts between adjacent pins.
Connect the PSU to the computer only after all measurements are correct.

When working with mains-powered power supplies, dangerous voltages may be present even after the PSU has been disconnected from mains power.

If you are not experienced with mains electricity, do not open or modify the PSU yourself.

Quick Reference

Commodore 64

Connector	Purpose
Power	+5V DC and 9V AC
A/V	Audio and video
Joystick Port 1	Digital joystick / I/O
Joystick Port 2	Digital joystick / I/O
Serial	Disk drives and printers
Datasette	Cassette interface
User Port	General-purpose I/O
Expansion Port	Cartridges and hardware expansions

Amiga

Connector / Feature	Information
External PSU	+5V, +12V and -12V
Red wire	+5V
Brown wire	+12V
White wire	-12V
Black wire	GND
Yellow wire	Shield

Remember: Connector pinouts and cable colours should always be verified against the specific computer, PSU and cable you are working with.

FAQ

Commodore 64 and Amiga Connector Pinouts

Commodore 64 and Amiga Connector Pinouts blog

FAQ

Commodore 64 and Amiga Connector Pinouts

Commodore 64 and Amiga Connector Pinouts blog