coco3: check for pal/ntsc bit in BASIC ROM, set hardware regs accordingly.

diff --git a/Kernel/platform-coco3/coco3.s b/Kernel/platform-coco3/coco3.s
index 1a17988..fe9b3bb 100644 (file)
--- a/Kernel/platform-coco3/coco3.s
+++ b/Kernel/platform-coco3/coco3.s
@@ -105,6 +105,10 @@ _irqrestore:                       ; B holds the data
 ; -----------------------------------------------------------------------------
 ; KERNEL MEMORY BANK
 ; -----------------------------------------------------------------------------
+       .area .data
+hz:    .db     0               ; Is machine in 50hz?
+
+       
             .area .text
 
 ;;;  Stuff to initialize *before* hardware
@@ -138,8 +142,17 @@ b@ sta     ,x+
         ;; set temporary screen up
        ldb     #%01000100      ; coco3 mode
        stb     $ff90
-       ldb     #%00000100      ; text / 8 lines per char row
-       stb     $ff98
+       ;; detect PAL or NTSC ROM
+       ldb     #$3f            ; put Super BASIC in mmu
+       stb     $ffae           ; 
+       lda     $c033           ; get BASIC's "mirror" of Video Reg
+       ldb     #$06            ; put Fuzix Kernel back in mmu
+       stb     $ffae           ;
+       anda    #$8             ; mask off 50 hz bit
+       sta     hz              ; save for future use
+       ;; continue setup of regs
+       ora     #%00000100      ; text / 8 lines per char row
+       sta     $ff98
        ldb     #%00010100      ; 80 column mode
        stb     $ff99
        ldd     #$b400/8        ; video at physical 0xb000