Digital Joysticks
Contents
Technical
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:
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.
Official Amstrad Joysticks
For the CPC+/GX4000, Amstrad seems to have also made Joypads (which work identically as joysticks).
Compatible Standard 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.
Incompatible Standard Joysticks
- 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).
Y-Cable
The original CPC models have only one joystick port, but can be used with 2 joysticks when using a Y-cable:
The CPC+/GX4000 have two digital joystick ports (which work equivalent to the Y-cable).
Is this true?
Some modification occured in the Amstrad "Atari" standard, especially for the PLUS range as Amstrad aimed the console market (GX4000) and used a politic of "Exclusive Hardware" like all console manufacturers of the time.
Not that it was changed compaired to Old CPC generation (yet few CPC games actually supported the 2 button feature, despite available.
Of course the Atari standard was originally a 1 button solution (Atari 8 bit consoles) but cxould easily be improuved to more buttons.
Sega Megadrives managed easily 6-8 button (Street Fighter 2 standard).
The most notable differences with other consoles using the Atari spec is with Sega systems (Master System and Megadrive). Yet simple re-cabling can be achieved thanks to proper adapter made simply :
- a pair of "Atari / 9 pin serial" connectors (one male and one female)
- and simply rewire between both as fit.
This allows to keep the original configuration of Sega compatible Pads/joysticks and benefit from the higher quality level from them.
A clever move may be to put such converter as a box with wires easily removable/changeable (not soldered, but inserted thank to proper solutions).
This would allows to configure more easily different configuration
- Sega Master system or MegaDrive/Genesis
- Mais even be suitable with Seag LightGuns if you can find a proper Power source.
As a result is may be a problem to find proper Joysticks for your PLUS/GX4000 with benefit from 2nd button, as Sega models won' t often fit and are often of a better quality/availability.
Other noable differences are compaired to Atari ST as the mouse can't fit unless powered. As a result, different Mouse standards appeared on Amstrad, using Joystick port Or Extension port. The same goes with lightphaser solutions.
Both could use Joystick port (added power suplly) or Extension port, or even the special LightGun port on Plus range (Is it powered ?).
by adding a power derivation on their Joystick port, Amstrad could have standardised it's technology and ease the CPC community.
Joystick Related stuff... Sega Controllers...
Analog Joysticks
The CPC+/GX4000 additionaly have an Analog Joystick Port.