initial commit

src/drivers/gfx_cgam.asm

@@ -0,0 +1,45 @@
+;
+; graphics drivers for CGA 640x200x2
+;
+%define GFX_MODE			0x06								; MCGA HiRes (B/W)
+%define GFX_WIDTH			640
+%define GFX_HEIGHT		200
+
+%define CGA_STRIDE    80
+%define CGA_ODD_BANK  0x2000
+%define BG16_SIZE     48
+
+; ce mode est entrelacé, un bit/pixel, 8 pixels par octet
+
+gfx_init:
+						; init graphics mode
+						mov 			ah, 0x00     			; AH=00h set video mode
+						mov				al, GFX_MODE
+						int 			0x10
+
+						call			gfx_background
+
+						ret
+
+; PutPixel(x=cx, y=dx, color=al) sur page bh
+gfx_putpixel:
+						mov  			ah, 0Ch
+						;mov  			al, 0Fh       ; couleur (0..15)
+						;mov  			bh, 00h       ; page
+						;mov  			cx, 100       ; x
+						;mov  			dx, 50        ; y
+						int  			10h
+						ret
+
+; draw background pattern
+gfx_background:
+						mov				ax,VIDEO_SEG
+						mov				es,ax
+						xor				di,di
+						mov				ax,0xaaaa
+						mov				cx,0x1000
+						rep				stosw
+						mov				ax,0x5555
+						mov				cx,0x1000			; 640/8/2
+						rep				stosw
+						ret