Digital Joysticks

The CPC joystick port is (more or less) based on the Atari-standard, for details on the pin-outs (and differences between Amstrad CPC and normal Atari/Commodore ports), see:

• CPC Joystick Port Pin-Outs

At software side, the joystick port is part of the keyboard matrix, accessed via the general purpose I/O port in the PSG chip, which is itself accessed indirectly via the 8255 chip.

• Amstrad JY-1/JY-2 joysticks

Amstrad's two-button joysticks. The quality isn't spectacular, so most CPC users tended to use third-party sticks, with only 1-button, but better quality. The JY-2 version contains a connector for a second joystick (equivalent to a built-in Y-cable).

The CPC+ and GX4000 were shipped with one or two digital joypads included. Technically, they work same as normal joysticks. But, they have two buttons. And, the GX4000 doesn't have a keyboard which could be used instead of a second fire button. In result, some CPC+/GX4000 games may rely on 2-button hardware, making them incompatible with regular 1-button joysticks.

All Atari-compatible digital joysticks with Single Fire Button and Four Direction switches should be usually working with the CPC. For example, classic Competition Pro joysticks or the Konix Speed King..

• Joysticks that do require 5V/GND supply (eg. for built-in auto-fire circuits) won't work on the CPC.
• Joysticks with 2-3 buttons may also be problematic (in the Atari standard, 2nd/3rd button are wired between POT0/POT1 and 5V).
• And, in lack of the POT inputs, any kind of analog devices (like Atari paddles) won't work on the CPC.
• Newer joysticks with PC-style 15pin or USB connector obviously won't fit to the CPCs 9pin port (unless one eliminates the electronics inside of those joysticks, and re-wires their botton/dirction switches directly to the CPCs joystick port).

The original CPC models have only one joystick port, but can be used with 2 joysticks when using a Y-cable:

• Joystick Y-cables

The CPC+/GX4000 have two digital joystick ports (which work equivalent to the Y-cable).

The CPCs digital joystick port is occasionally also misused to connect other hardware, known examples are: Some Lightguns: (Gunstick, West Phaser). Amstrad's Lightpen (Amstrad LP-1 light pen). And, various mouse interfaces (AMX Mouse, Atari-ST mouse adapter, Dk'tronics Mouse Interface, CPC-Mousepack 2.0, GEOS mouse).

On the original CPCs, the direction/button inputs can be reprogrammed as outputs (via PSG/PPI config). However, this will NOT work on the CPC+/GX4000's dual joystick ports - which include diodes (like normal joystick Y-cables).

• Digital Joystick Related

In the CPC world it is more common that a game supports both digital joystick and keyboard for those users who don't own joysticks.

There are some common keyboard configurations used:

• Cursor keys & SPACE
  • This configuration is often used and is great for the CPC6128 and Plus and playing using emulators.
  • This is not good for CPC 464 and 664 (which have uncomfortably arranged cursor keys)

• Q,A,O,P,SPACE - (Q up, A down, O left, P right, SPACE fire)
  • This is a good solution, and it's a sort of standard (used by many games).
  • Note: On french keyboards it'd be A,Q,O,P - anyways, the "UP" key is always Row8.Bit3, no matter if it's locally called "Q" (english QWERTY keyboard), or "A" (french AZERTY keyboard).

but because the decoding of the keys is done in software, normally by the OS, the bits in the keyboard matrix are actually the same).

Best would be to support joysticks, plus the above two keyboard mappings. Best to support them all at once (without needing the user select which one to use). In addition, it is also nice if the keys could be redefined but that is not necessary.

(*) Mind that Fire1 isn't supported on normal 1-button joysticks. When using it, also provide an alternate key on the keyboard.

The CPC+/GX4000 additionaly have an 15pin Analog Joystick Port, and a 6pin Lightgun socket (AUX).