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Code: Select all

        private int n = 0;

        public byte Read()
        {
            byte retval;

            retval = (n < 8) ? Convert.ToByte(state[n]) : (byte)1;

            n++;

            return retval;
        }

Code: Select all

        public void Write(byte value)
        {
            if ((value & 1) == 0)
            {
                latch = false;
                n = 0;
            }
            else
                latch = true;
        }

Code: Select all

        bool one = false;

        public void Write(byte value)
        {
            if ((value & 1) == 0)
            {
                if (one)
                {
                    latch = false;
                    n = 0;
                    one = false;
                }
            }
            else
            {
                latch = true;
                one = true;
            }
        }

Code: Select all

;$00 - temp joypad bit

ReadJoypads: 
              lda #$01               ;reset and clear strobe of joypad ports
              sta JOYPAD_PORT
              lsr
              tax                    ;start with joypad 1's port
              sta JOYPAD_PORT
              jsr ReadPortBits
              inx                    ;increment for joypad 2's port
ReadPortBits: ldy #$08
PortLoop:     pha                    ;push previous bit onto stack
              lda JOYPAD_PORT,x      ;read current bit on joypad port
              sta $00                ;check d1 and d0 of port output
              lsr                    ;this is necessary on the old
              ora $00                ;famicom systems in japan
              lsr
              pla                    ;read bits from stack
              rol                    ;rotate bit from carry flag
              dey
              bne PortLoop           ;count down bits left
              sta SavedJoypadBits,x  ;save controller status here always
              pha
              and #%00110000         ;check for select or start
              and JoypadBitMask,x    ;if neither saved state nor current state
              beq Save8Bits          ;have any of these two set, branch
              pla
              and #%11001111         ;otherwise store without select
              sta SavedJoypadBits,x  ;or start bits and leave
              rts
Save8Bits:    pla
              sta JoypadBitMask,x    ;save with all bits in another place and leave
              rts