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RELEASED
PM73122 AAL1GATOR-32
DATASHEET
PMC-1981419
ISSUE 7
32 LINK CES/DBCES AAL1 SAR PROCESSOR
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
386
FIFO overrun/underrun errors are reported by indicating error
status in the Extract/Insert FIFO Underrun/Overrun Interrupt Status
Register with the failing link identified.
These errors result in either the SBI_DROP_INTR or
SBI_ADD_INTR output being set.
These interrupts can only be cleared by reading the FIFO
overrun/underrun register with the failing link. Only one error can be
reported at a time. However errors are latched internally so that if
multiple errors occur, any pending errors will be reported when the first
one is cleared.
When an error is detected on a link, the link must be mapped back to a
tributary to determine which tributary had an error.
If a tributary has an underrun or overrun or depth check error, the
tributary must be reset. The tributary will automatically be reset if the
DC_EN bit is set AND the SYNC_LINK bit is not set on any tributaries
in INSBI. Otherwise the tributary must be reset by the processor by
writing the INS_TRIB_CTL or EXT_TRIB_CTL register for that
tributary.
If an SBI Alarm is detected to be changed on a particular link, then the
SBI_ALARM output is set to indicate SBI alarm change.
SBI_ALRM_STAT bit associated with that link indicates the current
state of the Extract SBI ALARM signal on the SBI tributary mapped to
this link. SBI_ALRM_INTn bit is also set to indicate that the SBI alarm
state has changed on the SBI tributary mapped to this link.
This SBI_ALRM_INTn interrupt can only be cleared by reading the
SBI ALARM Interrupt register.
The ALARM bit can be inserted into a tributary by setting the
SBI_ALRM_INS bit in the SBI Insert Bus Alarm Insert Register
associated with the link mapped to that tributary.
Buffer Depths Control:
Buffer depths are controlled via the MIN_DEPTH for T1 and E1
registers, MIN_DEPTH for DS3 registers, and T1, E1, DS3 Threshold
registers.