2. Getting Started
ÛZIATECH
19
Memory Address Map
Flash #1
Local (2Mbyte)
Reserved
Local DRAM
or STD
Local DRAM
BIOS Shadow
PCI or SRAM or STD
PCI or STD
PCI
Memory
STD
Local DRAM
or STD
PCI or STD
PCI or STD
PCI or STD
Local DRAM
FFFF FFFFh
FFC0 0000h
0800 0000h
0200 0000h
0100 0000h
0080 0000h
0010 0000h
000E 0000h
000D 8000h
F800 0000h
FFE0 0000h
000D 0000h
000C 8000h
000C 0000h
000A 0000h
Flash #2
Local (2Mbyte)
(4Gbyte)
(4Gbyte-128Mbyte)
(32Mbyte)
(16Mbyte)
(8Mbyte)
(1Mbyte)
(896Kbyte)
(864Kbyte)
(832Kbyte)
(128Mbyte)
(4Gbyte-2Mbyte)
(800Kbyte)
(768Kbyte)
(640Kbyte)
0
(4Gbyte-4Mbyte)
ZT8907
I/O CONFIGURATION
The ZT 8907 addresses up to 64 Kbytes of I/O using a 16-bit I/O address. The address
space is divided between I/O local to the board and I/O on the STD bus. Any I/O space
not reserved or occupied by a local I/O device is available for STD bus expansion.
During local I/O operations, the STD bus is held static to decrease system electrical
noise and power consumption.
Local and STD bus I/O data is transferred at a rate of up to 1 Mbyte/second for 8-bit
data and 2 Mbytes/second for 16-bit data. The ZT 8907 supports the STD bus wait
request signal, WAITRQ*, to interface to I/O boards with longer access time
requirements than those defined by the STD 32 specifications. The STD bus I/O