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MT9072
Data Sheet
184
Zarlink Semiconductor Inc.
Bit
Name
Functional Description
15-13
##
not used.
13
ONESEC
One Second Timer Status.
This bit toggles from low to high once every one second, and is
synchronous with the applied125 us frame pulse at pin FPi.
12
TWOSEC
Two Second Timer Status.
This bit toggles from low to high once every two seconds, and is
synchronous with the applied125 us frame pulse at pin FPi.
11
T1
Timer 1.
If one, indicates that a receive PCM30 link with non-normal operational CRC-4
frames (CSYNC=1 of register address Y10) has persisted for at least 100 ms. This bit is zero
when Timer 2 (T2 of register address Y11) is one. Refer to I.431 Section 5.9.2.2.3.
10
T2
Timer 2.
If one, indicates that a receive PCM30 link with normal operational CRC-4 frames
(CSYNC=0 of register address Y11) has persisted for at least 10 ms. This bit is cleared (zero)
when non-normal operational frames (CSYNC=1) occur. Refer to I.431 Section 5.9.2.2.3.
9
T400
400 ms Timer Status.
This is the 400 ms CRC-4 multiframe alignment timer. This bit initially
changes state from zero to one synchronously with the T8 (register address Y11) bit after the
T8 bit has consecutively toggled 50 times (400 ms). While this condition persists (T8=0101
etc.), the T400 bit continues to change state every 400 ms. The T400 bit is cleared (zero) with
the T8 bit when CRC-4 multiframe synchronization is acquired (CSYNC =0).
8
T8
8 ms Timer Status.
This is the 8 ms CRC-4 multiframe alignment timer. This bit initially
changes state from zero to one synchronously with the CRCRF (register address Y11) bit
when the received PCM30 link CRC-4 multiframe synchronization (CSYNC of register
address Y10) could not be found within the time out period of 8 ms after detecting basic frame
synchronization (BSYNC=0 of register address Y10). While this condition persists
(CRCRF=1), the T8 bit continues to change state every 8 ms. The T8 bit is cleared (zero) with
the CRCRF bit when CRC-4 multiframe synchronization is acquired (CSYNC =0).
7-5
###
not used.
4
CALN
CRC-4 Alignment 2ms Timer.
When CRC-4 multiframe alignment has not been achieved
(CSYNC=1 of register address Y10), this bit asynchronously changes state every 2 ms. When
CRC-4 multiframe alignment has been achieved (CSYNC =0), this bit still changes state every
2 ms, but is synchronous with the receive CRC-4 multiframe signal.
3
CRCRF
CRC-4 Reframe.
If one, indicates the received PCM30 link CRC-4 multiframe
synchronization (CSYNC of register address Y10) could not be found within the time out
period of 8 ms after detecting basic frame synchronization (BSYNC of register address Y10).
This bit is cleared (zero) when CRC-4 multiframe synchronization is acquired (CSYNC =0).
2
CRCS1
Receive CRC-4 Error Status One.
If one, the CRC-4 evaluation of the last received PCM30
link submultiframe 1 resulted in an error (the calculated C1,C2,C3,C4 CRC-4 remainder bits
did not match the received CRC-4 remainder C1,C2,C3,C4 bits). If zero, the last
submultiframe 1 was error free. Updated on a submultiframe 1 basis.
1
CRCS2
Receive CRC-4 Error Status Two.
If one, the CRC-4 evaluation of the last received PCM30
link submultiframe 2 resulted in an error (the calculated C1,C2,C3,C4 CRC-4 remainder bits
did not match the received CRC-4 remainder C1,C2,C3,C4 bits). If zero, the last
submultiframe 2 was error free. Updated on a submultiframe 2 basis.
0
(#)
not used.
Table 154 - CRC-4 Timers & CRC-4 Local Status (R Address Y11) (E1)