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MPC106 PCIB/MC User's Manual
MOTOROLA
2.2.5.11 System Error (SERR)
The PCI system error (SERR) signal is both an input and output signal on the MPC106.
2.2.5.11.1 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 MPC106 is acting as the initiator), or some other system error
(where the result is a catastrophic error) was detected.
Negated—Indicates no error.
2.2.5.11.2 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 MPC106) has
detected a catastrophic error.
Negated—Indicates no error.
2.2.5.12 Stop (STOP)
The stop (STOP) signal is both an input and output signal on the MPC106.
2.2.5.12.1 Stop (STOP)—Output
Following is the state meaning for STOP as an output signal.
State Meaning
Asserted—Indicates that the MPC106, acting as a PCI target, is
requesting that the initiator stop the current transaction.
Negated—Indicates that the current transaction can continue.
2.2.5.12.2 Stop (STOP)—Input
Following is the state meaning for STOP as an input signal.
State Meaning
Asserted—Indicates that a target is requesting that the PCI initiator
stop the current transaction.
Negated—Indicates that the current transaction can continue.
2.2.5.13 Target Ready (TRDY)
The target ready (TRDY) signal is both an input and output signal on the MPC106.
2.2.5.13.1 Target Ready (TRDY)—Output
Following is the state meaning for TRDY as an output signal.
State Meaning
Asserted—Indicates that the MPC106, acting as a PCI target, can
complete the current data phase of a PCI transaction. During a read,
the MPC106 asserts TRDY to indicate that valid data is present on
AD[31–0]. During a write, the MPC106 asserts TRDY to indicate
that it is prepared to accept data.