SECTION 4
PCI 9080
REGISTERS
PLX Technology, Inc., 1997
Page 71
Version 1.02
4.4.14 (LAS1BA; PCI:F4h, LOC:174h) Local Address Space 1 Local Base Address (Remap)
Register
Table 4-46. (LAS1BA; PCI:F4h, LOC:174h) Local Address Space 1 Local Base Address (Remap) Register
Field
Description
Read
Write
Value after Reset
0
Space 1 Enable. Value of 1 enables decoding of PCI addresses for Direct Slave
access to local space 1. Value of 0 disables decoding. If this bit is set to 0, the PCI
BIOS may not allocate (assign) the base address for Space 1.
Note:
Must be set to 1 for any Direct Slave access to Space 1.
Yes
Yes
0
1
Reserved.
Yes
No
0
3:2
If local space 1 is mapped into memory space, bits are not used. If mapped into
I/O space, bit is included with bits [31:4] for remapping.
Yes
Yes
0
31:4
Remap of PCI Address to Local Address Space 1 into a Local Address Space. The
bits in this register remap (replace) the PCI Address bits used in decode as the
Local Address bits.
Yes
Yes
0
Note:
Remap Address value must be multiple of Range (
not
the Range register).
4.4.15 (LBRD1; PCI:F8h, LOC:178h) Local Address Space 1 Bus Region Descriptor Register
Table 4-47. (LBRD1; PCI:F8h, LOC:178h) Local Address Space 1 Bus Region Descriptor Register
Field
Description
Read
Write
Value after Reset
1:0
Memory Space 1 Local Bus Width. Value of 00 indicates bus width of 8 bits, a value
of 01 indicates bus width of 16 bits and a value of 10 or 11 indicates bus width of 32
bits.
Yes
Yes
S = 01
J = 11
C = 11
5:2
Memory Space 1 Internal Wait States (data to data; 0-15 wait states).
Yes
Yes
0
6
Memory Space 1 Ready Input Enable. Value of 1 enables Ready input. Value of 0
disables Ready input.
Yes
Yes
0
7
Memory Space 1 BTERM# Input Enable. Value of 1 enables BTERM# input. Value
of 0 disables BTERM# input. If this bit is set to 0, PCI 9080 bursts four Lword
maximum at a time.
Yes
Yes
0
8
Memory Space 1 Burst Enable. Value of 1 enables bursting. Value of 0 disables
bursting. If burst is disabled, the local bus performs continuous single cycles for
burst PCI read/write cycles.
Yes
Yes
0
9
Memory Space 1 Prefetch Disable. If mapped into memory space, 0 enables read
prefetching. Value of 1 disables prefetching. If prefetching is disabled, PCI 9080
disconnects after each memory read.
Yes
Yes
0
10
Read Prefetch Count Enable. When set to 1 and memory prefetching is enabled,
PCI 9080 prefetches up to the number of Lwords specified in the prefetch count.
When set to 0, PCI 9080 ignores the count is ignored and continues prefetching
until terminated by the PCI bus.
Yes
Yes
0
14:11
Prefetch Counter. Number of Lwords to prefetch during memory read cycles
(0-15).
Yes
Yes
0
31:15
Reserved.
Yes
No
0