Intel 815 manual CURBASE-Cursor Base Address Register, CURPOS-Cursor Position Register

Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

R

20.4.2.CURBASE—Cursor Base Address Register

Memory Offset Address:	70084h
Default:	0000h
Attributes:	Read/Write

The cursor can only be read from System memory. This register is double buffered. The load register is transferred into the active register on the asserting edge of Vertical Sync.

31		29		28	8	7	0
		Reserved			Cursor Base Address Bits [28:08]		Reserved
	Bit				Descriptions
31:29			Reserved.
28:8			Cursor Base Address Bits [28:08]. These 21 bits provide most significant bits of a 29-bit physical
			address of the graphics non-cacheable system memory space where the 512 to 1 KB cursor data space
			for cursor is to be located. This is a physical address (No GTT translation).
7:0			Reserved.

20.4.3.CURPOS—Cursor Position Register

Memory Offset Address:	70088h
Default:	0000h
Attributes:	Read/Write

CURPOS is double buffered. The load register is transferred to the active register on the asserting edge of Vert Sync.

31	30	27	26	16
Y-Position		Reserved		Cursor Y-Position Magnitude Bits [10:0]
Sign Bit
15	14	11	10	0
X-Position		Reserved		Cursor X-Position Magnitude Bits [10:0]
Sign Bit
Bit				Descriptions
31	Cursor Y-Position Sign Bit. This bit provides the sign bit of a signed 12-bit value that specifies the
	horizontal position of cursor. (Default is 0).
30:27	Reserved.
26:16	Cursor Y-Position Magnitude Bits 10:0. This field provides the magnitude bits of a signed 12-bit
	value that specifies the vertical position of cursor. The sign bit of this value is provided by bit 31of this
	register. (Default is 0).
15	Cursor X-Position Sign Bit. This bit provides the sign bit of a signed 12-bit value that specifies the
	horizontal position of cursor. (Default is 0).
14:11	Reserved.
10:0	Cursor X-Position Magnitude Bits 10:0. These 11 bits provide the signed 12-bit value that specifies
	the horizontal position of cursor. The sign bit is provided by bit 15 of this register. (Default is 0).

362