LSI 53C875A Computer Hardware User Manual


 
PCI Bus Interface Signals 3-7
3.3.4 Arbitration Signals
Table 3.5 describes Arbitration signals.
3.3.5 Error Reporting Signals
Table 3.6 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.
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.
Table 3.6 Error Reporting Signals
Name PQFP BGA Type Strength Description
PERR/ 24 H2 S/T/
S
8mAPCI 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.
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.