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July\BBC/CODEass

This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.

Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.

Tape/disk: Home » Archimedes archive » Micro User » MU 1990-08.adf
Filename: July\BBC/CODEass
Read OK: ✔
File size: 05E8 bytes
Load address: FFFFFB43
Exec address: 6D3957D2
Duplicates

There is 1 duplicate copy of this file in the archive:

File contents
   10REM M/c Code - Listing I
   20REM by Mike Goldberg
   30REM (c) The Micro User
   40FOR L%=0 TO 2 STEP 2
   50P%=&3E00
   60[OPT L%
   70 JMP doBack
   80 JMP doDraw
   90 JMP doEras
  100 JMP doEnd
  110.doBack
  120 LDA #&20:STA &70
  130 LDA #&5D:STA &71
  140 LDX #0
  150 LDA #8:STA &79
  160.loop_b
  170 LDY #0
  180 LDA #32:STA &80
  190 LDA &4000,X:STA &72
  200 LDA &4001,X:STA &73
  210.draw_b
  220 LDA (&72),Y:STA (&70),Y
  230 INY:DEC &80:BNE draw_b
  240 CLC
  250 LDA &70:ADC #&20:STA &70
  260 LDA &71:ADC #&00:STA &71
  270 INX:INX:DEC &79:BNE loop_b
  280 RTS
  290.doDraw
  300 LDY #0:LDX #32
  310.draw_d
  320 LDA (&77),Y:STA (&74),Y
  330 INY:DEX:BNE draw_d
  340 CLC
  350 LDA &74:ADC #&40:STA &74
  360 LDA &75:ADC #&01:STA &75
  370 CLC
  380 LDA &77:ADC #&20:STA &77
  390 LDA &78:ADC #&00:STA &78
  400 DEC &76:BNE doDraw:RTS
  410.doEras
  420 LDY #0:LDX #32
  430.draw_e
  440 LDA #0:STA (&74),Y
  450 INY:DEX:BNE draw_e
  460 CLC
  470 LDA &74:ADC #&40:STA &74
  480 LDA &75:ADC #&01:STA &75
  490 DEC &76:BNE doEras:RTS
  500.doEnd
  510 LDA #8:STA &81
  520 LDA #&20:STA &74
  530 LDA #&5D:STA &75
  540.init
  550 LDA #6:STA &80
  560.again
  570 LDA #4:STA &70
  580 LDA &82:STA &77
  590 LDA &83:STA &78
  600.doAgain
  610 LDY #0:LDX #32
  620.draw_x
  630 LDA (&77),Y:STA (&74),Y
  640 INY:DEX:BNE draw_x
  650 CLC
  660 LDA &74:ADC #&40:STA &74
  670 LDA &75:ADC #&01:STA &75
  680 CLC
  690 LDA &77:ADC #&20:STA &77
  700 LDA &78:ADC #&00:STA &78
  710 DEC &70:BNE doAgain
  720 DEC &80:BNE again
  730 SEC
  740 LDA &74:SBC #&E0:STA &74
  750 LDA &75:SBC #&1D:STA &75
  760 DEC &81:BNE init:RTS
  770]:NEXT
  780*SAVE ACode4 3E00 3F00


� M/c Code - Listing I
� by Mike Goldberg
� (c) The Micro User
(� L%=0 � 2 � 2
2P%=&3E00
<[OPT L%
F JMP doBack
P JMP doDraw
Z JMP doEras
d JMP doEnd
n.doBack
x LDA #&20:STA &70
� LDA #&5D:STA &71
� LDX #0
� LDA #8:STA &79
�.loop_b
� LDY #0
� LDA #32:STA &80
� LDA &4000,X:STA &72
� LDA &4001,X:STA &73
�.draw_b
� LDA (&72),Y:STA (&70),Y
� INY:DEC &80:BNE draw_b
� CLC
� LDA &70:ADC #&20:STA &70
 LDA &71:ADC #&00:STA &71
 INX:INX:DEC &79:BNE loop_b
 RTS
".doDraw
, LDY #0:LDX #32
6.draw_d
@ LDA (&77),Y:STA (&74),Y
J INY:DEX:BNE draw_d
T CLC
^ LDA &74:ADC #&40:STA &74
h LDA &75:ADC #&01:STA &75
r CLC
| LDA &77:ADC #&20:STA &77
� LDA &78:ADC #&00:STA &78
� DEC &76:BNE doDraw:RTS
�.doEras
� LDY #0:LDX #32
�.draw_e
� LDA #0:STA (&74),Y
� INY:DEX:BNE draw_e
� CLC
� LDA &74:ADC #&40:STA &74
� LDA &75:ADC #&01:STA &75
� DEC &76:BNE doEras:RTS
�
.doEnd
� LDA #8:STA &81
 LDA #&20:STA &74
 LDA #&5D:STA &75
	.init
& LDA #6:STA &80
0
.again
: LDA #4:STA &70
D LDA &82:STA &77
N LDA &83:STA &78
X.doAgain
b LDY #0:LDX #32
l.draw_x
v LDA (&77),Y:STA (&74),Y
� INY:DEX:BNE draw_x
� CLC
� LDA &74:ADC #&40:STA &74
� LDA &75:ADC #&01:STA &75
� CLC
� LDA &77:ADC #&20:STA &77
� LDA &78:ADC #&00:STA &78
� DEC &70:BNE doAgain
� DEC &80:BNE again
� SEC
� LDA &74:SBC #&E0:STA &74
� LDA &75:SBC #&1D:STA &75
� DEC &81:BNE init:RTS
]:�
*SAVE ACode4 3E00 3F00
�
00000000  0d 00 0a 1a f4 20 4d 2f  63 20 43 6f 64 65 20 2d  |..... M/c Code -|
00000010  20 4c 69 73 74 69 6e 67  20 49 0d 00 14 16 f4 20  | Listing I..... |
00000020  62 79 20 4d 69 6b 65 20  47 6f 6c 64 62 65 72 67  |by Mike Goldberg|
00000030  0d 00 1e 18 f4 20 28 63  29 20 54 68 65 20 4d 69  |..... (c) The Mi|
00000040  63 72 6f 20 55 73 65 72  0d 00 28 12 e3 20 4c 25  |cro User..(.. L%|
00000050  3d 30 20 b8 20 32 20 88  20 32 0d 00 32 0c 50 25  |=0 . 2 . 2..2.P%|
00000060  3d 26 33 45 30 30 0d 00  3c 0b 5b 4f 50 54 20 4c  |=&3E00..<.[OPT L|
00000070  25 0d 00 46 0f 20 4a 4d  50 20 64 6f 42 61 63 6b  |%..F. JMP doBack|
00000080  0d 00 50 0f 20 4a 4d 50  20 64 6f 44 72 61 77 0d  |..P. JMP doDraw.|
00000090  00 5a 0f 20 4a 4d 50 20  64 6f 45 72 61 73 0d 00  |.Z. JMP doEras..|
000000a0  64 0e 20 4a 4d 50 20 64  6f 45 6e 64 0d 00 6e 0b  |d. JMP doEnd..n.|
000000b0  2e 64 6f 42 61 63 6b 0d  00 78 15 20 4c 44 41 20  |.doBack..x. LDA |
000000c0  23 26 32 30 3a 53 54 41  20 26 37 30 0d 00 82 15  |#&20:STA &70....|
000000d0  20 4c 44 41 20 23 26 35  44 3a 53 54 41 20 26 37  | LDA #&5D:STA &7|
000000e0  31 0d 00 8c 0b 20 4c 44  58 20 23 30 0d 00 96 13  |1.... LDX #0....|
000000f0  20 4c 44 41 20 23 38 3a  53 54 41 20 26 37 39 0d  | LDA #8:STA &79.|
00000100  00 a0 0b 2e 6c 6f 6f 70  5f 62 0d 00 aa 0b 20 4c  |....loop_b.... L|
00000110  44 59 20 23 30 0d 00 b4  14 20 4c 44 41 20 23 33  |DY #0.... LDA #3|
00000120  32 3a 53 54 41 20 26 38  30 0d 00 be 18 20 4c 44  |2:STA &80.... LD|
00000130  41 20 26 34 30 30 30 2c  58 3a 53 54 41 20 26 37  |A &4000,X:STA &7|
00000140  32 0d 00 c8 18 20 4c 44  41 20 26 34 30 30 31 2c  |2.... LDA &4001,|
00000150  58 3a 53 54 41 20 26 37  33 0d 00 d2 0b 2e 64 72  |X:STA &73.....dr|
00000160  61 77 5f 62 0d 00 dc 1c  20 4c 44 41 20 28 26 37  |aw_b.... LDA (&7|
00000170  32 29 2c 59 3a 53 54 41  20 28 26 37 30 29 2c 59  |2),Y:STA (&70),Y|
00000180  0d 00 e6 1b 20 49 4e 59  3a 44 45 43 20 26 38 30  |.... INY:DEC &80|
00000190  3a 42 4e 45 20 64 72 61  77 5f 62 0d 00 f0 08 20  |:BNE draw_b.... |
000001a0  43 4c 43 0d 00 fa 1d 20  4c 44 41 20 26 37 30 3a  |CLC.... LDA &70:|
000001b0  41 44 43 20 23 26 32 30  3a 53 54 41 20 26 37 30  |ADC #&20:STA &70|
000001c0  0d 01 04 1d 20 4c 44 41  20 26 37 31 3a 41 44 43  |.... LDA &71:ADC|
000001d0  20 23 26 30 30 3a 53 54  41 20 26 37 31 0d 01 0e  | #&00:STA &71...|
000001e0  1f 20 49 4e 58 3a 49 4e  58 3a 44 45 43 20 26 37  |. INX:INX:DEC &7|
000001f0  39 3a 42 4e 45 20 6c 6f  6f 70 5f 62 0d 01 18 08  |9:BNE loop_b....|
00000200  20 52 54 53 0d 01 22 0b  2e 64 6f 44 72 61 77 0d  | RTS.."..doDraw.|
00000210  01 2c 13 20 4c 44 59 20  23 30 3a 4c 44 58 20 23  |.,. LDY #0:LDX #|
00000220  33 32 0d 01 36 0b 2e 64  72 61 77 5f 64 0d 01 40  |32..6..draw_d..@|
00000230  1c 20 4c 44 41 20 28 26  37 37 29 2c 59 3a 53 54  |. LDA (&77),Y:ST|
00000240  41 20 28 26 37 34 29 2c  59 0d 01 4a 17 20 49 4e  |A (&74),Y..J. IN|
00000250  59 3a 44 45 58 3a 42 4e  45 20 64 72 61 77 5f 64  |Y:DEX:BNE draw_d|
00000260  0d 01 54 08 20 43 4c 43  0d 01 5e 1d 20 4c 44 41  |..T. CLC..^. LDA|
00000270  20 26 37 34 3a 41 44 43  20 23 26 34 30 3a 53 54  | &74:ADC #&40:ST|
00000280  41 20 26 37 34 0d 01 68  1d 20 4c 44 41 20 26 37  |A &74..h. LDA &7|
00000290  35 3a 41 44 43 20 23 26  30 31 3a 53 54 41 20 26  |5:ADC #&01:STA &|
000002a0  37 35 0d 01 72 08 20 43  4c 43 0d 01 7c 1d 20 4c  |75..r. CLC..|. L|
000002b0  44 41 20 26 37 37 3a 41  44 43 20 23 26 32 30 3a  |DA &77:ADC #&20:|
000002c0  53 54 41 20 26 37 37 0d  01 86 1d 20 4c 44 41 20  |STA &77.... LDA |
000002d0  26 37 38 3a 41 44 43 20  23 26 30 30 3a 53 54 41  |&78:ADC #&00:STA|
000002e0  20 26 37 38 0d 01 90 1b  20 44 45 43 20 26 37 36  | &78.... DEC &76|
000002f0  3a 42 4e 45 20 64 6f 44  72 61 77 3a 52 54 53 0d  |:BNE doDraw:RTS.|
00000300  01 9a 0b 2e 64 6f 45 72  61 73 0d 01 a4 13 20 4c  |....doEras.... L|
00000310  44 59 20 23 30 3a 4c 44  58 20 23 33 32 0d 01 ae  |DY #0:LDX #32...|
00000320  0b 2e 64 72 61 77 5f 65  0d 01 b8 17 20 4c 44 41  |..draw_e.... LDA|
00000330  20 23 30 3a 53 54 41 20  28 26 37 34 29 2c 59 0d  | #0:STA (&74),Y.|
00000340  01 c2 17 20 49 4e 59 3a  44 45 58 3a 42 4e 45 20  |... INY:DEX:BNE |
00000350  64 72 61 77 5f 65 0d 01  cc 08 20 43 4c 43 0d 01  |draw_e.... CLC..|
00000360  d6 1d 20 4c 44 41 20 26  37 34 3a 41 44 43 20 23  |.. LDA &74:ADC #|
00000370  26 34 30 3a 53 54 41 20  26 37 34 0d 01 e0 1d 20  |&40:STA &74.... |
00000380  4c 44 41 20 26 37 35 3a  41 44 43 20 23 26 30 31  |LDA &75:ADC #&01|
00000390  3a 53 54 41 20 26 37 35  0d 01 ea 1b 20 44 45 43  |:STA &75.... DEC|
000003a0  20 26 37 36 3a 42 4e 45  20 64 6f 45 72 61 73 3a  | &76:BNE doEras:|
000003b0  52 54 53 0d 01 f4 0a 2e  64 6f 45 6e 64 0d 01 fe  |RTS.....doEnd...|
000003c0  13 20 4c 44 41 20 23 38  3a 53 54 41 20 26 38 31  |. LDA #8:STA &81|
000003d0  0d 02 08 15 20 4c 44 41  20 23 26 32 30 3a 53 54  |.... LDA #&20:ST|
000003e0  41 20 26 37 34 0d 02 12  15 20 4c 44 41 20 23 26  |A &74.... LDA #&|
000003f0  35 44 3a 53 54 41 20 26  37 35 0d 02 1c 09 2e 69  |5D:STA &75.....i|
00000400  6e 69 74 0d 02 26 13 20  4c 44 41 20 23 36 3a 53  |nit..&. LDA #6:S|
00000410  54 41 20 26 38 30 0d 02  30 0a 2e 61 67 61 69 6e  |TA &80..0..again|
00000420  0d 02 3a 13 20 4c 44 41  20 23 34 3a 53 54 41 20  |..:. LDA #4:STA |
00000430  26 37 30 0d 02 44 14 20  4c 44 41 20 26 38 32 3a  |&70..D. LDA &82:|
00000440  53 54 41 20 26 37 37 0d  02 4e 14 20 4c 44 41 20  |STA &77..N. LDA |
00000450  26 38 33 3a 53 54 41 20  26 37 38 0d 02 58 0c 2e  |&83:STA &78..X..|
00000460  64 6f 41 67 61 69 6e 0d  02 62 13 20 4c 44 59 20  |doAgain..b. LDY |
00000470  23 30 3a 4c 44 58 20 23  33 32 0d 02 6c 0b 2e 64  |#0:LDX #32..l..d|
00000480  72 61 77 5f 78 0d 02 76  1c 20 4c 44 41 20 28 26  |raw_x..v. LDA (&|
00000490  37 37 29 2c 59 3a 53 54  41 20 28 26 37 34 29 2c  |77),Y:STA (&74),|
000004a0  59 0d 02 80 17 20 49 4e  59 3a 44 45 58 3a 42 4e  |Y.... INY:DEX:BN|
000004b0  45 20 64 72 61 77 5f 78  0d 02 8a 08 20 43 4c 43  |E draw_x.... CLC|
000004c0  0d 02 94 1d 20 4c 44 41  20 26 37 34 3a 41 44 43  |.... LDA &74:ADC|
000004d0  20 23 26 34 30 3a 53 54  41 20 26 37 34 0d 02 9e  | #&40:STA &74...|
000004e0  1d 20 4c 44 41 20 26 37  35 3a 41 44 43 20 23 26  |. LDA &75:ADC #&|
000004f0  30 31 3a 53 54 41 20 26  37 35 0d 02 a8 08 20 43  |01:STA &75.... C|
00000500  4c 43 0d 02 b2 1d 20 4c  44 41 20 26 37 37 3a 41  |LC.... LDA &77:A|
00000510  44 43 20 23 26 32 30 3a  53 54 41 20 26 37 37 0d  |DC #&20:STA &77.|
00000520  02 bc 1d 20 4c 44 41 20  26 37 38 3a 41 44 43 20  |... LDA &78:ADC |
00000530  23 26 30 30 3a 53 54 41  20 26 37 38 0d 02 c6 18  |#&00:STA &78....|
00000540  20 44 45 43 20 26 37 30  3a 42 4e 45 20 64 6f 41  | DEC &70:BNE doA|
00000550  67 61 69 6e 0d 02 d0 16  20 44 45 43 20 26 38 30  |gain.... DEC &80|
00000560  3a 42 4e 45 20 61 67 61  69 6e 0d 02 da 08 20 53  |:BNE again.... S|
00000570  45 43 0d 02 e4 1d 20 4c  44 41 20 26 37 34 3a 53  |EC.... LDA &74:S|
00000580  42 43 20 23 26 45 30 3a  53 54 41 20 26 37 34 0d  |BC #&E0:STA &74.|
00000590  02 ee 1d 20 4c 44 41 20  26 37 35 3a 53 42 43 20  |... LDA &75:SBC |
000005a0  23 26 31 44 3a 53 54 41  20 26 37 35 0d 02 f8 19  |#&1D:STA &75....|
000005b0  20 44 45 43 20 26 38 31  3a 42 4e 45 20 69 6e 69  | DEC &81:BNE ini|
000005c0  74 3a 52 54 53 0d 03 02  07 5d 3a ed 0d 03 0c 1a  |t:RTS....]:.....|
000005d0  2a 53 41 56 45 20 41 43  6f 64 65 34 20 33 45 30  |*SAVE ACode4 3E0|
000005e0  30 20 33 46 30 30 0d ff                           |0 3F00..|
000005e8

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