TechForum/DivMod03

Home » Archimedes archive » Acorn Computing » 1994 09.adf » 9409 » TechForum/DivMod03

TechForum/DivMod03

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 » Acorn Computing » 1994 09.adf » 9409
Filename:	TechForum/DivMod03
Read OK:	✔
File size:	0682 bytes
Load address:	0000
Exec address:	0000

Duplicates

There are 2 duplicate copies of this file in the archive:

Archimedes archive » Acorn Computing » 1994 09.adf » 9409 » TechForum/DivMod03
Archimedes archive » Archimedes World » AW-1996-03-Disc 2.adf » !AcornAns_AcornAns » September/FastDiv/Inspire/DivMod03
Archimedes archive » Archimedes World » AW-1995-05-Disc1.adf » AWMay95_1 » InTheMag/AcornAns/Inspire/DivMod03

File contents

   10REM >DivMod3
   20:
   30MODE 0
   40DIM mod 1024
   50a=0:b=1:c=2:d=3
   60FOR pass%=0 TO 3 STEP 3
   70P%=mod
   80[       OPT     pass%
   90        ADDS    a,b,b           ;remove iff b always +'ve
  100        RSBCS   b,b,#0          ;remove iff b always +'ve
  110        ADC     d,d,d           ;remove iff b always +'ve
  120        ADD     a,b,b,LSR #2
  130        ADD     a,a,a,LSR #4
  140        ADD     a,a,a,LSR #8
  150        ADD     a,a,a,LSR #16
  160        MOV     a,a,LSR #2
  170        ADD     c,a,a,ASL #1
  180        SUB     c,b,c
  190        CMP     c,#3
  200        ADDGE   a,a,#1          ;remove if don't need quotient
  210        SUBGE   c,c,#3          ;remove if don't need remainder
  220        MOVS    d,d,ASR #1      ;remove iff b always +'ve
  230        RSBCS   a,a,#0          ;remove iff b always +'ve or don't need quotient
  240        RSBCS   c,c,#0          ;remove iff b always +'ve or don't need remainder
  250        RSBCS   b,b,#0          ;remove iff don't need to preserve sign of b or b always +'ve
  260        STR     c, m%
  270        MOV     pc,R14
  280.m%     EQUD    0
  290]
  300NEXT
  310B%=0
  320REPEAT
  330  B%=-B%
  340  C%=USR(mod)
  350  D%=B%DIV3: E%=B%MOD3
  360  IF C%<>D% OR !m%<>E% PRINT"******************************************************************":VDU 7
  370  PRINT B%,C%,!m%;"  ", D%,E%
  380  IF C%<>D% OR !m%<>E% PRINT"******************************************************************":VDU 7
  390  B%=-B%
  400  C%=USR(mod)
  410  D%=B%DIV3: E%=B%MOD3
  420  IF C%<>D% OR !m%<>E% PRINT"******************************************************************":VDU 7
  430  PRINT B%,C%,!m%;"  ", D%,E%
  440  IF C%<>D% OR !m%<>E% PRINT"******************************************************************":VDU 7
  450  B%+=1
  460UNTIL FALSE
  470END


� >DivMod3
:
� 0
(� mod 1024
2a=0:b=1:c=2:d=3
<� pass%=0 � 3 � 3
F
P%=mod
P[       OPT     pass%
Z=        ADDS    a,b,b           ;remove iff b always +'ve
d=        RSBCS   b,b,#0          ;remove iff b always +'ve
n=        ADC     d,d,d           ;remove iff b always +'ve
x         ADD     a,b,b,LSR #2
�         ADD     a,a,a,LSR #4
�         ADD     a,a,a,LSR #8
�!        ADD     a,a,a,LSR #16
�        MOV     a,a,LSR #2
�         ADD     c,a,a,ASL #1
�        SUB     c,b,c
�        CMP     c,#3
�B        ADDGE   a,a,#1          ;remove if don't need quotient
�C        SUBGE   c,c,#3          ;remove if don't need remainder
�=        MOVS    d,d,ASR #1      ;remove iff b always +'ve
�T        RSBCS   a,a,#0          ;remove iff b always +'ve or don't need quotient
�U        RSBCS   c,c,#0          ;remove iff b always +'ve or don't need remainder
�a        RSBCS   b,b,#0          ;remove iff don't need to preserve sign of b or b always +'ve
        STR     c, m%
        MOV     pc,R14
.m%     EQUD    0
"]
,�
6B%=0
@�
J  B%=-B%
T  C%=�(mod)
^  D%=B%�3: E%=B%�3
hb  � C%<>D% � !m%<>E% �"******************************************************************":� 7
r  � B%,C%,!m%;"  ", D%,E%
|b  � C%<>D% � !m%<>E% �"******************************************************************":� 7
�  B%=-B%
�  C%=�(mod)
�  D%=B%�3: E%=B%�3
�b  � C%<>D% � !m%<>E% �"******************************************************************":� 7
�  � B%,C%,!m%;"  ", D%,E%
�b  � C%<>D% � !m%<>E% �"******************************************************************":� 7
�  B%+=1
�� �
��
�

00000000  0d 00 0a 0e f4 20 3e 44  69 76 4d 6f 64 33 0d 00  |..... >DivMod3..|
00000010  14 05 3a 0d 00 1e 07 eb  20 30 0d 00 28 0e de 20  |..:..... 0..(.. |
00000020  6d 6f 64 20 31 30 32 34  0d 00 32 13 61 3d 30 3a  |mod 1024..2.a=0:|
00000030  62 3d 31 3a 63 3d 32 3a  64 3d 33 0d 00 3c 15 e3  |b=1:c=2:d=3..<..|
00000040  20 70 61 73 73 25 3d 30  20 b8 20 33 20 88 20 33  | pass%=0 . 3 . 3|
00000050  0d 00 46 0a 50 25 3d 6d  6f 64 0d 00 50 19 5b 20  |..F.P%=mod..P.[ |
00000060  20 20 20 20 20 20 4f 50  54 20 20 20 20 20 70 61  |      OPT     pa|
00000070  73 73 25 0d 00 5a 3d 20  20 20 20 20 20 20 20 41  |ss%..Z=        A|
00000080  44 44 53 20 20 20 20 61  2c 62 2c 62 20 20 20 20  |DDS    a,b,b    |
00000090  20 20 20 20 20 20 20 3b  72 65 6d 6f 76 65 20 69  |       ;remove i|
000000a0  66 66 20 62 20 61 6c 77  61 79 73 20 2b 27 76 65  |ff b always +'ve|
000000b0  0d 00 64 3d 20 20 20 20  20 20 20 20 52 53 42 43  |..d=        RSBC|
000000c0  53 20 20 20 62 2c 62 2c  23 30 20 20 20 20 20 20  |S   b,b,#0      |
000000d0  20 20 20 20 3b 72 65 6d  6f 76 65 20 69 66 66 20  |    ;remove iff |
000000e0  62 20 61 6c 77 61 79 73  20 2b 27 76 65 0d 00 6e  |b always +'ve..n|
000000f0  3d 20 20 20 20 20 20 20  20 41 44 43 20 20 20 20  |=        ADC    |
00000100  20 64 2c 64 2c 64 20 20  20 20 20 20 20 20 20 20  | d,d,d          |
00000110  20 3b 72 65 6d 6f 76 65  20 69 66 66 20 62 20 61  | ;remove iff b a|
00000120  6c 77 61 79 73 20 2b 27  76 65 0d 00 78 20 20 20  |lways +'ve..x   |
00000130  20 20 20 20 20 20 41 44  44 20 20 20 20 20 61 2c  |      ADD     a,|
00000140  62 2c 62 2c 4c 53 52 20  23 32 0d 00 82 20 20 20  |b,b,LSR #2...   |
00000150  20 20 20 20 20 20 41 44  44 20 20 20 20 20 61 2c  |      ADD     a,|
00000160  61 2c 61 2c 4c 53 52 20  23 34 0d 00 8c 20 20 20  |a,a,LSR #4...   |
00000170  20 20 20 20 20 20 41 44  44 20 20 20 20 20 61 2c  |      ADD     a,|
00000180  61 2c 61 2c 4c 53 52 20  23 38 0d 00 96 21 20 20  |a,a,LSR #8...!  |
00000190  20 20 20 20 20 20 41 44  44 20 20 20 20 20 61 2c  |      ADD     a,|
000001a0  61 2c 61 2c 4c 53 52 20  23 31 36 0d 00 a0 1e 20  |a,a,LSR #16.... |
000001b0  20 20 20 20 20 20 20 4d  4f 56 20 20 20 20 20 61  |       MOV     a|
000001c0  2c 61 2c 4c 53 52 20 23  32 0d 00 aa 20 20 20 20  |,a,LSR #2...    |
000001d0  20 20 20 20 20 41 44 44  20 20 20 20 20 63 2c 61  |     ADD     c,a|
000001e0  2c 61 2c 41 53 4c 20 23  31 0d 00 b4 19 20 20 20  |,a,ASL #1....   |
000001f0  20 20 20 20 20 53 55 42  20 20 20 20 20 63 2c 62  |     SUB     c,b|
00000200  2c 63 0d 00 be 18 20 20  20 20 20 20 20 20 43 4d  |,c....        CM|
00000210  50 20 20 20 20 20 63 2c  23 33 0d 00 c8 42 20 20  |P     c,#3...B  |
00000220  20 20 20 20 20 20 41 44  44 47 45 20 20 20 61 2c  |      ADDGE   a,|
00000230  61 2c 23 31 20 20 20 20  20 20 20 20 20 20 3b 72  |a,#1          ;r|
00000240  65 6d 6f 76 65 20 69 66  20 64 6f 6e 27 74 20 6e  |emove if don't n|
00000250  65 65 64 20 71 75 6f 74  69 65 6e 74 0d 00 d2 43  |eed quotient...C|
00000260  20 20 20 20 20 20 20 20  53 55 42 47 45 20 20 20  |        SUBGE   |
00000270  63 2c 63 2c 23 33 20 20  20 20 20 20 20 20 20 20  |c,c,#3          |
00000280  3b 72 65 6d 6f 76 65 20  69 66 20 64 6f 6e 27 74  |;remove if don't|
00000290  20 6e 65 65 64 20 72 65  6d 61 69 6e 64 65 72 0d  | need remainder.|
000002a0  00 dc 3d 20 20 20 20 20  20 20 20 4d 4f 56 53 20  |..=        MOVS |
000002b0  20 20 20 64 2c 64 2c 41  53 52 20 23 31 20 20 20  |   d,d,ASR #1   |
000002c0  20 20 20 3b 72 65 6d 6f  76 65 20 69 66 66 20 62  |   ;remove iff b|
000002d0  20 61 6c 77 61 79 73 20  2b 27 76 65 0d 00 e6 54  | always +'ve...T|
000002e0  20 20 20 20 20 20 20 20  52 53 42 43 53 20 20 20  |        RSBCS   |
000002f0  61 2c 61 2c 23 30 20 20  20 20 20 20 20 20 20 20  |a,a,#0          |
00000300  3b 72 65 6d 6f 76 65 20  69 66 66 20 62 20 61 6c  |;remove iff b al|
00000310  77 61 79 73 20 2b 27 76  65 20 6f 72 20 64 6f 6e  |ways +'ve or don|
00000320  27 74 20 6e 65 65 64 20  71 75 6f 74 69 65 6e 74  |'t need quotient|
00000330  0d 00 f0 55 20 20 20 20  20 20 20 20 52 53 42 43  |...U        RSBC|
00000340  53 20 20 20 63 2c 63 2c  23 30 20 20 20 20 20 20  |S   c,c,#0      |
00000350  20 20 20 20 3b 72 65 6d  6f 76 65 20 69 66 66 20  |    ;remove iff |
00000360  62 20 61 6c 77 61 79 73  20 2b 27 76 65 20 6f 72  |b always +'ve or|
00000370  20 64 6f 6e 27 74 20 6e  65 65 64 20 72 65 6d 61  | don't need rema|
00000380  69 6e 64 65 72 0d 00 fa  61 20 20 20 20 20 20 20  |inder...a       |
00000390  20 52 53 42 43 53 20 20  20 62 2c 62 2c 23 30 20  | RSBCS   b,b,#0 |
000003a0  20 20 20 20 20 20 20 20  20 3b 72 65 6d 6f 76 65  |         ;remove|
000003b0  20 69 66 66 20 64 6f 6e  27 74 20 6e 65 65 64 20  | iff don't need |
000003c0  74 6f 20 70 72 65 73 65  72 76 65 20 73 69 67 6e  |to preserve sign|
000003d0  20 6f 66 20 62 20 6f 72  20 62 20 61 6c 77 61 79  | of b or b alway|
000003e0  73 20 2b 27 76 65 0d 01  04 19 20 20 20 20 20 20  |s +'ve....      |
000003f0  20 20 53 54 52 20 20 20  20 20 63 2c 20 6d 25 0d  |  STR     c, m%.|
00000400  01 0e 1a 20 20 20 20 20  20 20 20 4d 4f 56 20 20  |...        MOV  |
00000410  20 20 20 70 63 2c 52 31  34 0d 01 18 15 2e 6d 25  |   pc,R14.....m%|
00000420  20 20 20 20 20 45 51 55  44 20 20 20 20 30 0d 01  |     EQUD    0..|
00000430  22 05 5d 0d 01 2c 05 ed  0d 01 36 08 42 25 3d 30  |".]..,....6.B%=0|
00000440  0d 01 40 05 f5 0d 01 4a  0c 20 20 42 25 3d 2d 42  |..@....J.  B%=-B|
00000450  25 0d 01 54 0f 20 20 43  25 3d ba 28 6d 6f 64 29  |%..T.  C%=.(mod)|
00000460  0d 01 5e 16 20 20 44 25  3d 42 25 81 33 3a 20 45  |..^.  D%=B%.3: E|
00000470  25 3d 42 25 83 33 0d 01  68 62 20 20 e7 20 43 25  |%=B%.3..hb  . C%|
00000480  3c 3e 44 25 20 84 20 21  6d 25 3c 3e 45 25 20 f1  |<>D% . !m%<>E% .|
00000490  22 2a 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |"***************|
000004a0  2a 2a 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |****************|
*
000004d0  2a 2a 2a 22 3a ef 20 37  0d 01 72 1d 20 20 f1 20  |***":. 7..r.  . |
000004e0  42 25 2c 43 25 2c 21 6d  25 3b 22 20 20 22 2c 20  |B%,C%,!m%;"  ", |
000004f0  44 25 2c 45 25 0d 01 7c  62 20 20 e7 20 43 25 3c  |D%,E%..|b  . C%<|
00000500  3e 44 25 20 84 20 21 6d  25 3c 3e 45 25 20 f1 22  |>D% . !m%<>E% ."|
00000510  2a 2a 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |****************|
*
00000550  2a 2a 22 3a ef 20 37 0d  01 86 0c 20 20 42 25 3d  |**":. 7....  B%=|
00000560  2d 42 25 0d 01 90 0f 20  20 43 25 3d ba 28 6d 6f  |-B%....  C%=.(mo|
00000570  64 29 0d 01 9a 16 20 20  44 25 3d 42 25 81 33 3a  |d)....  D%=B%.3:|
00000580  20 45 25 3d 42 25 83 33  0d 01 a4 62 20 20 e7 20  | E%=B%.3...b  . |
00000590  43 25 3c 3e 44 25 20 84  20 21 6d 25 3c 3e 45 25  |C%<>D% . !m%<>E%|
000005a0  20 f1 22 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  | ."*************|
000005b0  2a 2a 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |****************|
*
000005e0  2a 2a 2a 2a 2a 22 3a ef  20 37 0d 01 ae 1d 20 20  |*****":. 7....  |
000005f0  f1 20 42 25 2c 43 25 2c  21 6d 25 3b 22 20 20 22  |. B%,C%,!m%;"  "|
00000600  2c 20 44 25 2c 45 25 0d  01 b8 62 20 20 e7 20 43  |, D%,E%...b  . C|
00000610  25 3c 3e 44 25 20 84 20  21 6d 25 3c 3e 45 25 20  |%<>D% . !m%<>E% |
00000620  f1 22 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |."**************|
00000630  2a 2a 2a 2a 2a 2a 2a 2a  2a 2a 2a 2a 2a 2a 2a 2a  |****************|
*
00000660  2a 2a 2a 2a 22 3a ef 20  37 0d 01 c2 0b 20 20 42  |****":. 7....  B|
00000670  25 2b 3d 31 0d 01 cc 07  fd 20 a3 0d 01 d6 05 e0  |%+=1..... ......|
00000680  0d ff                                             |..|
00000682

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