Random demo
Random demo
Random demo
Listing 1
10000 FOR X=1664 TO 1755
10010 READ Y:POKE X,Y:NEXT X
10020 DATA 104,104,133,213,104,133
10030 DATA 212,104,104,168,104,104
10040 DATA 170,169,3,192,0,240,5,10
10050 DATA 10,136,144,247,141,219,6
10060 DATA 160,255,138,208,31,168
10070 DATA 173,219,6,73,255,49,212
10080 DATA 145,212,200,173,219,6,49
10090 DATA 212,136,17,212,145,211,200
10100 DATA 192,255,208,231,169,0,145
10110 DATA 212,96,173,219,6,73,255,49
10120 DATA 212,145,212,136,173,219,6
10130 DATA 49,212,200,17,212,145,212
10140 DATA 136,208,233,169,0,145,212
10150 DATA 96,96  
Listing 2
0000         0100        *=   $0680     ;ASSEMBLY LOCATION.
             0110 ;
0680 68      0120 INIT   PLA            ;REMOVE # OF ARCS.
0681 68      0130        PLA            ;GET MSB OF MISSILE
0682 85D5    0140        STA  $D5       ; RAM AND STORE IT.
0684 68      0150        PLA            ;GET LSB OF MISSILE
0685 85D4    0160        STA  $04       ; RAM AND STORE IT.
0687 68      0170        PLA            ;DISCARD MSB AND PUT
0688 68      0180        PLA            ; LSB OF THE MISSILE
0689 A8      0190        TAY            ;  TO MOVE INTO 'Y'.
068A 68      0200        PLA            ;DISCARD MSB AND PUT
068B 68      0210        PLA            ; LSB OF DIRECTTION
068C AA      0220        TAX            ;  TO MOVE INTO 'X'.
068D A903    0230        LDA  #$03      ;SET UP BIT MASK.
068F C000    0240 ADJUST CPY  #$00      ;MASK ADJUSTED?
0691 F005    0250        BEQ  PPM       ;SAVE MASK IF O.K.
0693 0A      0260        ASL  A         ;SHIFT MASK TO POINT
0694 0A      0270        ASL  A         ; TO NEXT MISSILE.
0695 88      0280        DEY
0696 90F7    0290        BCC  ADJUST    ;CHECK IF DONE.
0698 8DDB06  0300 PUTMSK STA  MASK      ;SAVE MISSILE MASK.
069B A0FF    0310        LDY  #$FF      ;SETUP MOVE OFFSET.
069D 8A      0320        TXA            ;RESTORE DIRECTION.
069E D01F    0330        BNE  DOWN      ;MOVE UP IF ZERO.
06A0 A8      0340        TAY            ;FIX OFFSET FOR UP.
             0350
06A1 ADDB06  0360 UP     LDA  MASK      ;GET MISSILE MASK
06A4 49FF    0370        EOR  #$FF      ; AND INVERT IT.
06A6 3104    0380        AND  ($D4),Y   ;REMOVE THE EXISTING
06A8 9104    0390        STA  ($D4),Y   ; MISSILE BITS.
06AA C8      0400        INY            ;POINT TO NEW BITS. 
06AB ADDB0674I0          LDA  MASK      ;GET MISSILE MASK
06AE 3104    0420        AND  ($D4),Y   ; AND EXISTING BITS.
06B0 88      0430        DEY            ;POINT TO DESTINATION.
06B1 1104    0440        ORA  ($D4),Y   ;ADD ONLY MISSILE
06B3 9104    0450        STA  ($D4),Y   ; BITS AND SAVE.
06B5 C8      0460        INY            ;POINT BACK AGAIN.
06B6 C0FF    0470        CPY  #$FF      ;CHECK IF LAST
06B8 D0E7    0480        BNE  UP        ; MISSILE BITE.
06BA A900    0490        LDA  #$00      ;ZERO OUT OLD
06BC 8104    0500        STA  ($D4),Y   ; EDGE CONTENTS.
06BE 60      0510        RTS            ;ALL DONE.
             0520
06BF AD0806  0530 DOWN   LDA  MASK      ;GET MISSILE MASK
06C2 49FF    0540        EOR  #$FF      ; AND INVERT IT.
06C4 3104    0550        AND  ($D4),Y   ;REMOVE EXISTING
06C6 9104    0560        STA  ($D4),Y   ; MISSILE BITS.
06C8 88      0570        DEY            ;POINT TO NEW BITS.
06C9 ADDB06  0580        LDA  MASK      ;GET MISSILE MASK
06CC 3104    0590        AND  ($D4),Y   ; AND EXISTING BITS.
06CE C8      0600        INY            ;POINT TO DESTINATION.
06CF 1104    0610        ORA  ($D4).Y   ;ADD ONLY MISSILE
06D1 9104    0620        STA  ($D4),Y   ; BITS AND SAVE.
06D3 88      0630        DEY            ;CHECK FOR LAST
06D4 D0E9    0640        BNE  DOWN      ; MISSILE BYTE.
06D6 A900    0650        LDA  #$00      ;ZERO OUT OLD
06D8 9104    0660        STA  ($D4),Y   ; EDGE CONTENTS.
06DA 60      0670        RTS            ;ALL DONE.
             0680 ;
06DB 60      0690 MASK   RTS            ;TEMPORARY STORAGE.  

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