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>> Software programming for the computer Sprinter Thread views: 93

dirtyfly
(stranger )
2002/03/06 04:39

Screen memory location on the sprinter

Hi all

Any one knows what adresses are the memory locations of the screen in sprinter ? for graphic modes and 256 color

thanks

Denis Parinov VIP

(Sprinter Team)
2002/03/06 18:59

Re: Screen memory location on the sprinter new

[re: dirtyfly]

Today, Estex DSS support four screen modes:

text 40x32 with 16 colors (mode 02h);
text 80x32 with 16 colors (mode 03h);
graph 320x256 with 256 colors (mode 81h);
graph 640x256 with 16 colors (mode 82h);

The default mode for the DSS is 80x32 text mode, if your program need
another screen mode then you need to switch it by DSS function 50h
(SETVMOD). Also before switching you should ask DSS and save current screen
mode by function 51h (GETVMOD). And when you program will be ready to
finished, restore it by 50h (SETVMOD).

for example:


	LD	C,51h	;get screen mode

	RST	10h

	LD	C,A	;move mode number to register C

	PUSH	BC	;and save to stack BC (B - active page, C - mode)

	.

	. 		;your program

	.



	POP	BC	;restore mode from stack

	LD	A,C	;move screen mode to register A

	LD	C,50h	;set screen mode

	RST	10h

	LD	C,41h	;terminate program

	RST	10h

DSS has some functions for outing symbols and strings at the text screen.
But for the graphic modes you need to write it yourself.

for example:


	LD	HL,STRING	;pointer to the string

	LD	C,5Ch		;outing string

	RST	10h



STRING	DB	"Thank you for using my program..."

	DB	13,10		;CR and LF codes

	DB	0		;End of string

For painting at the graphic screen memory, you need to set one of three
memory frames 04000h-07FFFh, 08000h-0BFFFh, 0C000h-0FFFFh. It can be made
by set value 50h to the ports 0A2h, 0C2h or 0E2h. Don't forgot about STACK
place!

for example: if you want to set one point then routine for 81h mode will
look like:


; HL - x coord

; DE - y coord

	IN	A,(0E2h)	;read page number

	LD	C,A		;move it to C (save)

	LD	A,50h		;page of video RAM

	OUT	(0E2h),A	;set it to third frame 0C000-0FFFFh

	LD	A,E		;Y-coord (0...255)

	OUT	(89h),A		;set to Y-port

	LD	DE,0C000h	;frame address

	ADD	HL,DE		;add x-coord

	LD	A,255		;point color (�� 0 �� 255) (index to palette)

	LD	(HL),A		;put pixel

	LD	A,C		;restore page number

	OUT	(0E2h)		;set it

It's all. Note: Before it, you need to set required colors at the
palette.
More information about it you can read in Sprinter architecture or ask us
here.