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MPC8240 Integrated Processor User’s Manual
Detailed Signal Descriptions
2.2.1.10.2 Target Ready (TRDY)—Input
Following is the state meaning for TRDY as an input signal.
State Meaning
Asserted—Indicates another PCI target is able to complete the
current data phase of a transaction. If the MPC8240 is the initiator of
the transaction, it latches the data (on a read) or cycles the data on a
write.
Negated—Indicates a wait cycle needed by a target. If the MPC8240
is the initiator of the transaction, it waits to latch the data (on a read)
or continues to drive the data (on a write).
2.2.1.11 Parity Error (PERR)
The PCI parity error (PERR) signal is both an input and output signal on the MPC8240. See
Section 13.2.3.2, “Parity Error (PERR),” and Section 4.8.2, “Error Enabling and Detection
Registers,” for more information on how the MPC8240 is set up to report parity errors. The
PCI initiator drives PERR on read operations; the PCI target drives PERR on write
operations.
2.2.1.11.1 Parity Error (PERR)—Output
Following is the state meaning for PERR as an output signal.
State Meaning
Asserted—Indicates that the MPC8240, acting as a PCI agent,
detected a data parity error.
Negated—Indicates no error.
2.2.1.11.2 Parity Error (PERR)—Input
Following is the state meaning for PERR as an input signal.
State Meaning
Asserted—Indicates that another PCI agent detected a data parity
error while the MPC8240 was sourcing data (the MPC8240 was
acting as the PCI initiator during a write, or was acting as the PCI
target during a read).
Negated—Indicates no error.
2.2.1.12 System Error (SERR)
The PCI system error (SERR) signal is both an input and output signal on the MPC8240. It
is an open-drain signal and can be driven by multiple devices on the PCI bus. Refer to
Section 13.2.3.1, “System Error (SERR),” and Section 4.8.2, “Error Enabling and
Detection Registers,” for more information on how the MPC8240 drives and reports system
errors.
Summary of Contents for MPC8240
Page 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Page 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Page 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Page 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Page 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Page 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Page 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Page 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Page 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Page 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Page 516: ...16 14 Watchpoint Trigger Applications ...
Page 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Page 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Page 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...