cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 271

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

Revision 0.8
USB Register Descriptions
5.5.3.3
Index
Type
Reset Value
5.5.3.4
Index
Type
Reset Value
PAR_
ERR
15
15:10
15
Bit
9
8
7
6
5
4
3
2
1
0
SERR_
STS
14
14
Command (USBC_PCI_CMD)
Status (USBC_PCI_STS)
Name
RSVD
FB2B_EN (RO)
SERR
WS_CTL
PAR
VGA_SNP_EN
(RO)
MEMW_INV
SPC_CYC
MSTR_EN
MEM
IO
RCVD_
MSTR_
ABT_
STS
13
13
04h
R/W
0000h
06h
R/W
0280h
RSVD
RCVD_
TRGT_
ABT_
STS
12
12
TRGT_
ABT_
SIG_
STS
11
11
Description
Reserved. Set to 0.
Fast Back-to-Back Enable (Read Only). USB only acts as a master to a single device,
so this functionality is not needed. It is always disabled (must always be set to 0).
System Error. USB asserts SERR# when it detects an address parity error.
0: Disable; 1: Enable.
Wait Cycle Control. USB does not need to insert a wait state between the address and
data on the AD lines. It is always disabled (bit is set to 0).
Parity Error. USB asserts PERR# when it is the agent receiving data and it detects a
data parity error. 0: Disable; 1: Enable.
VGA Palette Snoop Enable (Read Only). USB does not support this function. It is
always disabled (bit is set to 0).
Memory Write and Invalidate: Allow USB to run Memory Write and Invalidate com-
mands. 0: Disable; 1: Enable.
The Memory Write and Invalidate commands only occur if the cache line size is set to
32 bytes and the memory write is exactly one cache line.
This bit is ignored by the GeodeLink Adapter and hence the setting is a ‘don’t care’.
Special Cycles. USB does not run special cycles on PCI. It is always disabled (bit is
set to 0).
PCI Master Enable. Allow USB to run PCI master cycles. 0: Disable; 1: Enable.
Memory Space. Allow USB to respond as a target to memory cycles. 0: Disable; 1:
Enable.
I/O Space. Allow USB to respond as a target to I/O cycles. 0: Disable; 1: Enable.
DEVSEL_TIME DATA_
(Continued)
10
10
USBC_PCI_CMD Bit Descriptions
USBC_PCI_CMD Register Map
USBC_PCI_STS Register Map
FB2B_
EN
9
9
SERR
PAR
8
8
271
FB2B
WS_
CTL
7
7
PAR
6
6
VGA_
SNP_
EN
5
5
MEMW
_INV
4
4
RSVD
SPC_
CYC
3
3
MSTR_
EN
2
2
MEM
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