LSI 53C875A Manual De Usuario
PCI Bus Interface Signals
3-7
3.3.4 Arbitration Signals
describes Arbitration signals.
3.3.5 Error Reporting Signals
describes the Error Reporting signals.
Table 3.5
Arbitration Signals
Name
PQFP
BGA
Type
Strength
Description
REQ/
148
E6
O
8 mA PCI Request indicates to the system arbiter that this agent
desires use of the PCI bus. This is a point-to-point signal.
Every master has its own REQ/ signal.
Every master has its own REQ/ signal.
GNT/
147
D6
I
N/A
Grant indicates to the agent that access to the PCI bus
has been granted. This is a point-to-point signal. Every
master has its own GNT/ signal.
has been granted. This is a point-to-point signal. Every
master has its own GNT/ signal.
Table 3.6
Error Reporting Signals
Name
PQFP
BGA
Type
Strength
Description
PERR/
24
H2
S/T/
S
8 mA PCI Parity Error may be pulsed active by an agent that
detects a data parity error. PERR/ can be used by any
agent to signal data corruption. However, on detection of
a PERR/ pulse, the central resource may generate a
nonmaskable interrupt to the host CPU, which often
implies the system is unable to continue operation once
error processing is complete.
agent to signal data corruption. However, on detection of
a PERR/ pulse, the central resource may generate a
nonmaskable interrupt to the host CPU, which often
implies the system is unable to continue operation once
error processing is complete.
SERR/
143
E7
O
8 mA PCI System Error is an open drain output used to report
address parity errors as well as critical errors other than
parity.
parity.