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use mul40 routine instead of doing the multiplication myself

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git-svn-id: svn://svn.cc65.org/cc65/trunk@117 b7a2c559-68d2-44c3-8de9-860c34a00d81
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cpg 2000-06-23 22:05:59 +00:00
parent 70dbbb542f
commit 7b944cae11
1 changed files with 2 additions and 16 deletions
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18
libsrc/atari/cputc.s
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@ -7,7 +7,7 @@
.export _cputcxy, _cputc .export _cputcxy, _cputc
.export plot, cputdirect, putchar .export plot, cputdirect, putchar
.import popa, _gotoxy .import popa, _gotoxy, mul40
.include "atari.inc" .include "atari.inc"
@ -70,22 +70,8 @@ plot: ldy COLCRS
putchar: putchar:
pha ; save char pha ; save char
lda #0
sta tmp4
lda ROWCRS lda ROWCRS
asl a jsr mul40
rol tmp4
asl a
rol tmp4 ; row * 4
adc ROWCRS
bcc L1
inc tmp4 ; row * 5
L1: asl a
rol tmp4 ; row * 10
asl a
rol tmp4
asl a
rol tmp4 ; row * 40
L3: clc L3: clc
adc SAVMSC ; add start of screen memory adc SAVMSC ; add start of screen memory
sta ptr4 sta ptr4