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DS33M30/M31/M33 DATA SHEET
Rev: 010809
14 of 21
1.4.3.2 Line DS3/E3 Formatter (Optional)
Insertion of all overhead for M23 DS3, C-bit parity DS3, G.751 E3, and G.832 E3
Automatic or manual generation of RDI/RAI and FEBE/REI
Fully programmable automatic AIS insertion upon detection of an outbound Drop Telecom Bus alarm
indication (DALARM), VC-4 LOP, VC-4 AIS-P, STS-1/AU-3/TU-3 LOP, and/or STS-1 SPE/VC-3 AIS-P
Automatic generation of RDI/RAI and FEBE/REI
Programmable error insertion of framing errors, parity errors, and FEBE/REI errors
All DS3/E3 overhead fields can be sourced from the externally controlled transmit DS3/E3 overhead input
port
Insertion of HDLC data stream into DS3 path maintenance data link (PMDL), G.751 E3 national bit, or
G.832 E3 NR or GC bytes
Insertion of FEAC data into DS3 FEAC bit or G.751 E3 alarm bit
Insertion of trail trace access point identifier into G.832 E3 TR byte
M23 DS3 C-bits programmable as payload or overhead
Formatter pass-through mode with programmable DS3 P-bit correction for DS3/E3 line terminating
equipment (LTE) applications
1.4.3.3 FEAC Controller
One controller per port at the Receive DS3/E3 framer and Transmit DS3/E3 Formatter
Designed to handle multiple FEAC codewords without Host intervention
Receive FEAC automatically validates incoming codewords and stores them in a 4-byte FIFO
Transmit FEAC can be programmed to send one code word, one code word continuously, or two different
code words back-to-back to send DS3 Line Loopback commands
Terminates the FEAC port in DS3 C-Bit Parity mode or either the Sn or A bit in G.751 E3 mode
1.4.3.4 Receive B3ZS/HDB3 Decoder
Software programmable B3ZS/HDB3 or AMI decoding
Detection of loss of signal (LOS) and receipt of B3ZS/HDB3 codewords
Detection and accumulation of bipolar violations (BPV), code violations (CV), and excessive zeroes
occurrences (EXZ)
1.4.3.5 Transmit B3ZS/HDB3 Encoder
Software programmable B3ZS/HDB3 or AMI decoding
Programmable insertion of bipolar violations (BPV), code violations (CV), and excessive zeroes
occurrences (EXZ)
1.4.4 Loopback
Line analog terminal loopback—ALB (transmit LIU/line output to receive LIU/line input)
Line facility loopback—LLB (receive LIU/line output to transmit LIU/line input)
Diagnostic terminal loopback—DLB (transmit formatter output to receive framer input)
Payload loopback—PLB (receive framer output to transmit formatter input)
STS-3/STM-1 interface loopback—SLB (Outbound Drop Telecom Bus input to Inbound Add Telecom Bus
output)
Simultaneous line facility loopback (LLB) and diagnostic terminal loopback (DLB)
Optionally AIS (unframed all-ones, UA1, or framed AIS) can be inserted in the normal data stream during a
line (LLB), framer diagnostic (DLB), payload (PLB), or STS-3/STM-1 loopback (SLB) mode
1.5
Virtual Concatenation (VCAT) (DS33M31 and DS33M33 only)
Up to three VCG engines
1.5.1 SONET/SDH VCAT/LCAS
Supports up to three VC-3 in one VCG (per ITU-T G.707)
Supports differential delay compensation up to 200ms