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 180kΩ to Vcc.
Software using Analog Joystick
- Tennis Cup 2 ( Cartridge ) allows player 2 to use Analog port.
