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optimize charcode conversion, shorter and faster now :)

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This commit is contained in:
mrdudz 2015-10-12 18:53:55 +02:00
parent aed0549760
commit 4557e8d004
1 changed files with 5 additions and 15 deletions
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20
libsrc/c64/soft80_cputc.s
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@ -49,7 +49,7 @@ L1: cmp #$0D ; LF?
; codes $00-$1f are control codes which are not printable and thus may
; give undefined result.
tay
bpl L10
bpl @L10
; codes $80-$ff must get converted like this:
; $80-$9f -> dont care (control codes)
@ -57,21 +57,11 @@ L1: cmp #$0D ; LF?
; $c0-$df -> $60-$7f
; $e0-$ff -> $00-$1f
; extra check for petscii codes 160-191, these have been moved to
; 0-31 in the charset
and #%11100000
cmp #%10100000
bne @sk
tya
and #%00011111
bpl L10 ; branch always
@sk:
tya
ora #%01000000 ; $40
clc
adc #$20
and #$7F
L10:
adc #%00100000 ; $20
and #%01111111 ; $7f
@L10:
; entry point for direct output of a character. the value passed in
; akku must match the offset in the charset.