Connector:Analogue joystick (CPC Plus only)

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Analogue Joystick Port (15 Pin SUB-D, female) (CPC Plus only)

The Analogue CPC+ Joystick port is somewhat similar to standard PC Joystick ports - with some important differences:

  • 5V and GND are exchanged with each other, and,
  • on CPC+ the buttons must be connected to a "select" line (instead of to GND).
  • The ADC hardware in the CPC works only with 180kΩ potentiometers (unlike the software counters in PCs, which works with different types, in range 10K...300kΩ, or so)

Caution - there is no resistor in the supply lines - the 5V/GND pins connect directly to the computers 2.4 Ampere power supply - so, there's a good chance that the CPCs reversed polarity will destroy any electronics (electrolyte capacitors, auto-fire circuits, etc) in connected PC joysticks.

 Pin CPC+                    PC                      ________________________
 1   GND (Pot common)        +5V (Pot common)       |                        |
 2   /Fire1                  Player1.Fire1          | 8  7  6  5  4  3  2  1 |
 3   X1                      Player1.PotX (lt/rt)    \ 15 14 13 12 11 10  9 /
 4   /Stick1 (button common) GND (button common)      \____________________/
 5   +5V                     GND
 6   Y1                      Player1.PotY (up/dn)
 7   /Fire2                  Player1.Fire2
 8   GND (Pot common)        +5V (Soundblaster: GND)
 9   GND (Pot common)        +5V
 10  /Fire1                  Player2.Fire 1
 11  X2                      Player2.PotX (lt/rt)
 12  /Stick2 (button common) GND (Soundblaster: Midi TxD)
 13  Y2                      Player2.PotY (up/dn)
 14  /Fire2                  Player2.Fire 2
 15  GND (Pot common)        +5V (Soundblaster: Midi RxD)
  • Two analogue joysticks could be connected by using an Y-cable. The Fire signals are the same as for the normal (digital) joystick port. Joystick 1 buttons should be connected to Pin 2,4,6, and joystick 2 buttons to Pin 10,12,14. Like the digital Joystick Y-cables the analog Y-cable should have diodes in the button lines (there are no diodes between pins 7+14 and 2+10 the mainboard).
  • The A/D inputs have an input range of 0V (data = 00) to 2.5V (data = 3Fh), and an input impedance of 180k to Vcc.

Softwares using Analog Joystick

Compatible Models