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Routines |
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Used by the routine at 54942.
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| 54999 | LD C,31 | Load 31 (Kempston port number) into A | ||||||
| 55001 | IN A,(C) | Read byte from port 31 (i.e. read state of joystick) | ||||||
| 55003 | BIT 0,A | If joystick moved right... | ||||||
| 55005 | CALL NZ,55103 | ...store a RIGHT input from control device | ||||||
| 55008 | BIT 1,A | If joystick moved left... | ||||||
| 55010 | CALL NZ,55100 | ...store a LEFT input from control device | ||||||
| 55013 | BIT 2,A | If joystick moved down... | ||||||
| 55015 | CALL NZ,55109 | ...store a DOWN input from control device | ||||||
| 55018 | BIT 3,A | If joystick moved up... | ||||||
| 55020 | CALL NZ,55106 | ...store an UP input from control device | ||||||
| 55023 | BIT 4,A | If fire button pressed... | ||||||
| 55025 | CALL NZ,55112 | ...store a FIRE input from control device | ||||||
| 55028 | LD A,(HL) | Return stored joystick movement in A | ||||||
| 55029 | RET | Return | ||||||
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