Intel 815 11. GR10Address Mapping, Reserved To Local Memory Enable, VGA Buffer/Memory Map Select

Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

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9.3.11.GR10Address Mapping

I/O (and Memory Offset) Address:					3CFh (Index=10h)
Default:					00h
Attributes:					R/W
7				5	4	3	2	1	0
				Reserved	Paging to	VGA	Packed	Linear	Page
					LM	Buffer /	Mode	Mapping	Mapping
						Memory	Enable
						Map
		Bit				Description
	7:5		Reserved.
	4		Page to Local Memory Enable.
			Used Only if GR10(0) = 1 {Paging enabled} and (GR10(1) = 1 or GR10(2) = 1) {Either packed mode or
			Linear mode is enabled) and GR10(3) = 0 {VGA Buffer selected}
			0	= Page to VGA Buffer.
			1	= Page to Physical Local Memory.
	3		VGA Buffer/Memory Map Select.
			0	= VGA Buffer (default)
			1	= Memory Map.
	2		Packed Mode Enable.
			0	= Address and data translation are bused register settings (default)
			1	= Forced extended pack pixel address translation. In page mapping mode, register GR06 selects the
				video memory address.
	1		Linear Mapping (PCI).
			0	= Disable (default)
			1	= Enable
	0		Page Mapping Enable. This mode allows the mapping of the VGA space allocated in main memory
			(non local video memory) mode or all of local memory space through the [A0000:AFFFF] window
			(Using bit 4 of this register), which is a 64KB page. An internal address is generated using GR11[6:0]
			as the address line [22:16] extension to A[15:2].
			0	= Disable (default)
			1	= Enable

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