Chapter 2. Signal Descriptions and Clocking
2-15
Detailed Signal Descriptions
2.2.1.12.1 System Error (SERR)—Output
Following is the state meaning for SERR as an output signal.
State Meaning
Asserted—Indicates that an address parity error, a target-abort (when
the MPC8240 is acting as the initiator), or some other system error
(where the result is a catastrophic error) was detected.
Negated—Indicates no error.
2.2.1.12.2 System Error (SERR)—Input
Following is the state meaning for SERR as an input signal.
State Meaning
Asserted—Indicates that a target (other than the MPC8240) has
detected a catastrophic error.
Negated—Indicates no error.
2.2.1.13 Stop (STOP)
The stop (STOP) signal is both an input and output signal on the MPC8240. Refer to
Section 7.4.3.2, “Target-Initiated Termination,” for more information on the use of the
STOP signal.
2.2.1.13.1 Stop (STOP)—Output
Following is the state meaning for STOP as an output signal.
State Meaning
Asserted—Indicates that the MPC8240, acting as a PCI target, is
requesting that the initiator stop the current transaction.
Negated—Indicates that the current transaction can continue.
2.2.1.13.2 Stop (STOP)—Input
Following is the state meaning for STOP as an input signal.
State Meaning
Asserted—Indicates that when the MPC8240 is acting as a PCI
initiator, it is receiving a request from the target to stop the current
transaction.
Negated—Indicates that the current transaction can continue.
2.2.1.14 Interrupt Request (INTA)—Output
Following is the state meaning for INTA. This signal is primarily used when the MPC8240
is programmed in agent mode.
State Meaning
Asserted—Indicates that the MPC8240 is requesting an interrupt on
the PCI bus. These interrupts are caused by the on-chip DMA
controller and the message unit.
Negated—Indicates that the MPC8240 is not requesting an interrupt
on the PCI bus.
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 ...