Sharp MZ-3500 service manual Graphic V-RAM Address, Crtc block diagram

M-3500

CH48 -	0 For 40 digit display	Relation between VRAM address and screen
	1 : For 80 digit display
		16-bit structure
	There is a 40/80 digit switching signal I/O port
	in the gate array of CSP1and CSP2, but, the I/O	Graphic
	signal called CH48 is provided apart from the I/O
		address
	port.	map for
I 08/16 -	I/O port inside CSP1and CSP2.	400 rasters

7) Graphic V-RAM Address

Relation between VRAM address and screen (640 x 200 dots)

	8-bit structure
t lnntn0000"~^	~
0050	Graphic
00\0
OOFO	address
	map for
	200 rasters
LXH)
liytr

bOb\ir —

CRTC block diagram

Color graphic VRAM PWB (option)