Commodore 64 Troubleshooting
23 May 2020
The C64 Joystick fix
5 June 2020
The most annoying thing about games?
... Having to change the joystick port!
Problem solved with the Switcher
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You may have happened to have the joystick in port 2 and load a game that requires the joystick on port 1 (or vice versa).
To avoid having to unplug and reattach the connector on the correct port there is new hardware to be inserted between the Commodore ports and the joystick so you can easily swap ports by pressing just a button.
There are different types on the market, this is a self-built and you can find the diagrams on the network, the operation is simple, by pressing the button the digital and analog signals coming from the joystick, mouse, pen or paddle are exchanged, by pressing the button again. everything will return to normal mode. The led on the button indicates whether it is in normal or inverted mode.
How does it work...
Operation is quite simple. the micro controls the mode through an input with a button, if normal all the input lines of the respective ports will reflect those relating to the outputs, while if inverted it will control the one of the opposite door.
The only exception for the analog inputs of the ports (pot Ay, Ax and By, Bx), these are exchanged with a dedicated integrated AGD774, a quadruple switch which, controlled by the micro, inverts the analog ports (Ay> By Ax> Bx)
JOYSTICK HOLDER C64
| PIN | PORT 1 | PORT 2 | DESCRIPTION |
|---|---|---|---|
| 1 | JOY A0 | JOY B0 | ON |
| 2 | JOY A1 | JOY B1 | BELOW |
| 3 | JOY A2 | JOY B2 | LEFT |
| 4 | JOY A3 | JOY B3 | RIGHT |
| 5 | POT AY | POT BY | INPUT Y |
| 6 | PULS. TO | PULS. B. | FIRE |
| 7 | +5 VOLT | +5 VOLT | 100mA MAX |
| 8 | GND | GND | |
| 9 | POT AX | POT BX | INPUT X |
Mirco G
geek and handyman
