Computed pixel aspect ratio (PAR) by presuming a display aspect ratio (DAR) of 4...

git-svn-id: svn://svn.cc65.org/cc65/trunk@5017 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/libsrc/geos/devel/geos-tgi.s b/libsrc/geos/devel/geos-tgi.s
index d7484b47f7cf8528d5ef903cf3d31879b0b5ffbd..247920df18d27c6e96e82f576a536f77c9f786a1 100644 (file)
--- a/libsrc/geos/devel/geos-tgi.s
+++ b/libsrc/geos/devel/geos-tgi.s
@@ -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