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S/UNI-JET Data Sheet
Released
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
222
Register 390H: TTB Control
Bit
Type
Function
Default
Bit 7
R/W
ZEROEN
0
Bit 6
R/W
RRAMACC
0
Bit 5
R/W
RTIUIE
0
Bit 4
R/W
RTIMIE
0
Bit 3
R/W
PER5
0
Bit 2
R/W
TNULL
1
Bit 1
R/W
NOSYNC
0
Bit 0
R/W
Reserved
0
Reserved
The reserved bit should be set to logic zero for proper operation.NOSYNC
The NOSYNC bit disables synchronization to the Trail Trace message. When NOSYNC is set
high, synchronization is disabled and the bytes of the Trail Trace message are captured by the
TTB in a circular buffer. When NOSYNC is set low, the TTB synchronizes to the byte with
the most significant bit set high and places that byte in the first location in the capture buffer
page.
TNULL
The transmit null (TNULL) bit controls the insertion of all-zeros into the outgoing Trail Trace
message. The null insertion should be used when microprocessor accesses that change the
outgoing trail trace message are being performed. When TNULL is set high, an all-zeros byte
is inserted to the transmit stream. When this bit is set low, the contents of the transmit trace
buffer are sent.
PER5
The receive trace identifier persistency bit (PER5) controls the number of times that
persistency check is made in order to accept the received message. When this bit is set high,
five identical message required in order to accept the message. When this bit set low, three
unchanged consecutive messages are required.
RTIMIE
The receive trace identifier mismatch interrupt enable (RTIMIE) controls the activation of the
interrupt output when comparison between the accepted trace identifier message and the
expected trace identifier message changes state from match to mismatch and vice versa.
When RTIMIE is set high, changes in match state will activate the interrupt output. When
RTIMIE set low, trail trace message match state changes will not affect INTB.