W90221X Winbond Electronics Corp America, W90221X Datasheet - Page 140

• Manufacturer Part Number: W90221X
• Description: Pa-risc Embedded Controller
• Manufacturer: Winbond Electronics Corp America

6.5
The W90221X provides an ISA-like bus, called the WIO bus, for those low speed devices
such as ROM, Flash, or other 8/16-bit I/O devices. The bus shares the 32-bit address/data
bus, the 4-bit command/byte enable bus, and the INTD# signal with PCI bus. The WIO bus
supports only 8-bit memory (like ROM/Flash) and 8- or 16-bit I/O devices attached on it. Also,
the WIO bus provides up to 16 Mbytes (consisting of twenty-four address lines) space for
memory and 64K (consisting of sixteen address lines) for I/O devices. Two base registers,
containing 8-bit base address for memory and 16-bit for I/O, specify the starting address of
the WIO memory space and I/O space. The I/O address space 0xf0000360 ~ 0xf0000367 is
allocated for three 16-bit configuration registers of the WIO bus controller.
W90221X version 0.6
Port Address
BA + 0x360
BA + 0x362
BA + 0x364
BA + 0x366
WIO BUS CONTROLLER
WIOBASE
WMBASE
Symbol
CFG
-
Access
R/W
R/W
R/W
R/W
Configuration register
WIO I/O space base register
WIO ROM space base register
Reserved
Description
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