;**	6845 CRT CONTROLLER DEFINITIONS
;

	NOLIST
;
;		  RESTRICTED RIGHTS LEGEND
;		  ------------------------
;
;	     "Use, duplication, or disclosure by the
;	government is subject to restrictions as set forth
;	in paragraph (b) (3) (B) of the Rights in Technical
;	Data and Computer Software clause in DAR
;	7-104.9(a).  Contractor/manufacturer is Zenith
;	Data Systems Corporation of Hilltop Road, St.
;	Joseph, Michigan 49085.
;
	LIST

;	PORT DISPLACEMENTS

CRTREG	EQU	0			;CRT-C REGISTER SELECT
CRTDAT	EQU	1			;CRT-C DATA

;	CRT-C INTERNAL REGISTERS
;	NOTE: A "*" INDICATES THE REGISTER VALUE READ/WRITTEN IS
;	      ONE LESS THAN ACTUAL VALUE.

CRTHT	EQU	0			;* HORIZONTAL TOTAL
CRTHD	EQU	1			;  HORIZONTAL DISPLAY
CRTHSP	EQU	2			;* HORIZONTAL SYNC POSITION
CRTSW	EQU	3			;  SYNC WIDTH
CRTSWWH	EQU	00001111B		;   HORIZONTAL
CRTSWWV	EQU	11110000B		;   VERTICAL
CRTVT	EQU	4			;* VERTICAL TOTAL
CRTVTA	EQU	5			;  VERTICAL TOTAL ADJUST
CRTVD	EQU	6			;  VERTICAL DISPLAY
CRTVSP	EQU	7			;* VERTICAL SYNC POSITION
CRTIS	EQU	8			;  INTERLACE AND SKEW
CRTISIS	EQU	00000001B		;   INTERLACE SYNC
CRTISISV EQU	00000011B		;   INTERLACE AND SYNC
CRTISDS1 EQU	00010000B		;   DISPTMG ONE CHAR SKEW
CRTISDS2 EQU	00100000B		;   DISPTMG TWO CHAR SKEW
CRTISDNO EQU	00110000B		;   NON-OUTPUT
CRTISCS1 EQU	01000000B		;   CURSOR ONE CHAR SKEW
CRTISCS2 EQU	10000000B		;   CURSOR TWO CHAR SKEW
CRTISCNO EQU	11000000B		;   NON-OUTPUT
CRTMRA	EQU	9			;  MAXIMUM RASTER ADDRESS
CRTCSR	EQU	10			;  CURSOR START RASTER
CRTCSRSRA EQU	00011111B		;   START RASTER ADDRESS
CRTCSRND EQU	00100000B		;   NOT DISPLAYED
CRTCSRBS EQU	00100000B		;   BLINK SLOW (WITH CRTCSRCB)
CRTCSRCB EQU	01000000B		;   BLINK ENABLE
CRTCER	EQU	11			;  CURSOR END RASTER
CRTSAH	EQU	12			;  START ADDRESS (MSB)
CRTSAL	EQU	13			;  START ADDRESS (LSB)
CRTCH	EQU	14			;  CURSOR (MSB)
CRTCL	EQU	15			;  CURSOR (LSB)
CRTLPH	EQU	16			;  LIGHT PEN ADDRESS (MSB)
CRTLPL	EQU	17			;  LIGHT PEN ADDRESS (LSB)