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Computed pixel aspect ratio (PAR) by presuming a display aspect ratio (DAR) of 4/3 for a classic CRT and using the given driver resolutions as storage aspect ratio (SAR).

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git-svn-id: svn://svn.cc65.org/cc65/trunk@5017 b7a2c559-68d2-44c3-8de9-860c34a00d81
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ol.sc 2011-05-02 11:23:30 +00:00
parent 4aa00e84e1
commit d72d373e83
1 changed files with 8 additions and 5 deletions
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13
libsrc/geos/devel/geos-tgi.s
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@ -48,7 +48,7 @@ yres: .word 200 ; Y resolution
pages: .byte 1 ; Number of screens available
.byte 8 ; System font X size
.byte 8 ; System font Y size
.word $100 ; Aspect ratio: 1.0
aspect: .word $00D4 ; Aspect ratio (based on 4/3 display)
; Next comes the jump table. With the exception of IRQ, all entries must be
; valid, and may point to an RTS for test versions (function not implemented).
@ -139,10 +139,13 @@ INSTALL:
; check for VDC version and update register $19 value
@L80:
lda #<640
ldx #>640
sta xres
stx xres+1
; double the x resolution and halve the aspect ratio
asl xres
rol xres+1
lsr aspect+1
ror aspect
; update number of available screens