DS3170 DS3/E3 Single-Chip Transceiver
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Bit 11: Automatic Downstream AIS Disable (AAISD) – When 0, the presence of an LOS, OOF, or AIS condition
will cause downstream AIS to be inserted. When 1, the presence of an LOS, OOF, or AIS condition will not cause
downstream AIS to be inserted.
Bit 10: Error Count Control (ECC) – When 0, framing errors, P-bit parity errors, C-bit parity errors, and far-end
block errors will not be counted if an OOF or AIS condition is present.
P-bit parity errors, C-bit parity errors, and
far-end block errors will also not be counted during the DS3 frame in which an OOF condition is terminated, and
the next DS3 frame. When 1, framing errors, P-bit parity errors, C-bit parity errors, and far-end block errors will be
counted regardless of the presence of an OOF or AIS condition.
Bits 9 to 8: Framing Error Count Control (FECC[1:0]) – These two bits control the type of framing error events
that are counted.
00 = count OOF occurrences (counted regardless of the setting of the ECC bit).
01 = count M bit and F bit errors.
10 = count only F bit errors.
11 = count only M bit errors.
Bit 7: Receive Alarm Indication on LOF Enable (RAILE) – When 0, an LOF condition does not affect the receive
alarm indication signal (RAI). When 1, an LOF condition will cause the transmit DS3 X-bits to be set to zero if
transmit automatic RDI is enabled.
Bit 6: Receive Alarm Indication on LOS Disable (RAILD) – When 0, an LOS condition will cause the transmit
DS3 X-bits to be set to zero if transmit automatic RDI is enabled. When 1, an LOS condition does not affect the RAI
signal.
Bit 5: Receive Alarm Indication on SEF Disable (RAIOD) – When 0, an SEF condition will cause the transmit
DS3 X-bits to be set to zero if transmit automatic RDI is enabled. When 1, an SEF condition does not affect the RAI
signal.
Bit 4: Receive Alarm Indication on AIS Disable (RAIAD) – When 0, an AIS condition will cause the transmit DS3
X-bits to be set to zero if transmit automatic RDI is enabled. When 1, an AIS condition does not affect the RAI
signal.
Bit 3: Receive Overhead Masking Disable (ROMD) – When 0, the DS3 overhead positions in the outgoing DS3
payload will be marked as overhead by RDEN. When 1, the DS3 overhead positions in the outgoing DS3 payload
will be marked as data by RDEN. When this bit is set to one, the COVHD bit is ignored.
Bits 2 to 1: LOF Integration Period (LIP[1:0]) – These two bits determine the OOF integration period for
declaring LOF.
00 = OOF is integrated for 3 ms before declaring LOF
01 = OOF is integrated for 2 ms before declaring LOF
10 = OOF is integrated for 1 ms before declaring LOF.
11 = LOF is declared at the same time as OOF.
Bit 0: Force Framer Resynchronization (FRSYNC) – A 0 to 1 transition forces an OOF, SEF, and OOMF
condition. The bit must be cleared and set to one again to force another resynchronization Note: The OOMF
condition is created by failing the most recent four data path M-bit checks.
Register Name:
T3.RSR1
Register Description:
T3 Receive Status Register #1
Register Address:
124h
Bit #
15
14
13
12
11
10
9
8
Name
Reserved
--
Reserved
T3FM
AIC
IDLE
RUA1
Bit #
7
6
5
4
3
2
1
0
Name
OOMF
--
SEF
LOF
RDI
AIS
OOF
LOS
Bit 11: T3 Framing Format Mismatch (T3FM) – This bit indicates the DS3 framer is programmed for a framing
format (C-bit or M23) that is different than the format indicated by the AIC bit in the incoming DS3 signal.