Motorola MVME2300 Series manual Wpen, Iom, MSOFF3

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Raven PCI Bridge ASIC

				WPEN						Write-Post Enable. If set, write-posting is enabled for the
										corresponding MPC slave.
				MEM						PCI Memory Cycle. If set, the corresponding MPC slave
										will generate transfers to or from PCI memory space.
										When clear, the corresponding MPC slave will generate
										transfers to or from PCI I/O space using the addressing
										mode defined by the IOM field.
				IOM						PCI I/O Mode. If set, the corresponding MPC slave will
										generate PCI I/O cycles using spread addressing as
										defined in the section on Generating PCI Memory and I/O
										Cycles. When clear, the corresponding MPC slave will
										generate PCI I/O cycles using contiguous addressing.
										This field only has meaning when the MEM bit is clear.
MPC Slave Offset/Attribute (3) Registers
Address											MSOFF3/MSATT3 - $FEFF005C
Bit												1	1	1	1	1	1	1	1	1	1	2	2	2	2	2	2	2	2	2	2	3	3
	0	1	2	3	4	5	6		7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1
Name							MSOFF3																					MSATT3
																										REN	WEN		WPEN				IOM
Operation									R/W												R					R/W	R/W	R	R/W	R	R	R	R/W
Reset								$8000													$00					1	1	0	0	0	0	0	0
				MSOFF3						MPC Slave Offset. Contains a 16-bit offset that is added
										to the upper 16 bits of the MPC address to determine the
										PCI address used for transfers from the MPC bus to PCI.

This offset allows PCI resources to reside at addresses that would not normally be visible from the MPC bus. It is initialized to $8000 to facilitate a zero-based access to PCI space.

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