coco3: add basic gfx_read/gfx_write routine.

diff --git a/Kernel/platform-coco3/videoll.s b/Kernel/platform-coco3/videoll.s
index c40c07b..3bc021b 100644 (file)
--- a/Kernel/platform-coco3/videoll.s
+++ b/Kernel/platform-coco3/videoll.s
@@ -53,6 +53,28 @@ a@   ldb     ,u+
        puls    x,y,u,pc
 
 
+;
+;      These routines wortk in both 256x192x2 and 128x192x4 modes
+;      because everything in the X plane is bytewide.
+;
+_video_write:
+       pshs u
+       bsr vidptr
+       tfr x,y                 ; So we can use y to get at the w/h
+       leax 4,x                ; Move on to data space
+vwnext:
+       lda 2,y
+       pshs u
+vwline:
+       ldb ,x+
+       stb ,u+
+       deca
+       bne vwline
+       puls u
+       leau 32,u
+       dec ,y
+       bne vwnext
+       puls u,pc
 
 
 vidptr:
@@ -64,7 +86,28 @@ vidptr:
        ldd     ,x++            ; X
        leau    d,u
        rts
-
+       
+;
+;      FIXME - fold read/write into one self modifier
+;
+_video_read:
+       pshs u
+       bsr vidptr
+       tfr x,y                 ; So we can use y to get at the w/h
+       leax 4,x                ; Move on to data space
+vrnext:
+       lda 2,y                 ; a counts our copy along the scan line
+       pshs u
+vrline:
+       ldb ,u+                 ; b does our data
+       stb ,x+
+       deca
+       bne vrline
+       puls u                  ; step down a line
+       leau 32,u
+       dec ,y                  ; use the buffer directly for line count
+       bne vrnext
+       puls u,pc               ; and done
 
 ;;; void video_cmd( char *rle_data );
 _video_cmd: