millfork/include/c64_cia.mfk

// Hardware addresses for C64

//   CIA1
byte cia1_pra       @$DC00
byte cia1_prb       @$DC01
byte cia1_ddra      @$DC02
byte cia1_ddrb      @$DC03
byte cia2_pra       @$DD00
byte cia2_prb       @$DD01
byte cia2_ddra      @$DD02
byte cia2_ddrb      @$DD03

inline asm void cia_disable_irq() {
    LDA #$7f
    LDA $dc0d
    LDA $dd0d
    LDA $dc0d
    LDA $dd0d
}


inline void vic_bank_0000() {
    cia2_ddra = $C0
    cia2_pra = $C0
}

inline void vic_bank_4000() {
    cia2_ddra = $C0
    cia2_pra = $80
}

inline void vic_bank_8000() {
    cia2_ddra = $C0
    cia2_pra = $40
}

inline void vic_bank_C000() {
    cia2_ddra = $C0
    cia2_pra = $00
}