DS3170N+ Maxim Integrated Products, DS3170N+ Datasheet - Page 93

• Manufacturer Part Number: DS3170N+
• Description: IC TXRX DS3/E3 100-CSBGA
• Manufacturer: Maxim Integrated Products

Specifications of DS3170N+

• Function: Single-Chip Transceiver
• Interface: DS3, E3
• Number Of Circuits: 1
• Voltage - Supply: 3.135 V ~ 3.465 V
• Current - Supply: 120mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 100-LBGA
• Includes: DS3 Framers, E3 Framers, HDLC Controller, On-Chip BERTs
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -

DS3170 DS3/E3 Single-Chip Transceiver
FA1 and FA2 are the Frame Alignment bytes. EM is the Error Monitoring byte used for path error monitoring. TR is
the Trail Trace byte used for end-to-end connectivity verification. MA is the Maintenance and Adaptation byte used
for far-end path status and performance monitoring.
NR is the Network Operator byte allocated for network operator maintenance purposes. GC is the General Purpose
Communications Channel byte allocated for user communications purposes.
10.6.8.2 Transmit G.832 E3 Frame Generation
G.832 E3 frame generation receives the incoming payload data stream, and overwrites all of the E3 overhead byte
locations.
The first two bytes of the first row in the frame are overwritten with the frame alignment bytes FA1 and FA2, which
have a value of F6h and 28h respectively.
The first byte in the second row of the frame is overwritten with the EM byte which is a BIP-8 calculated over all of
the bytes of the previous frame after all frame processing (frame generation, error insertion, overhead insertion,
and AIS generation) has been performed. The first byte in the third row of the frame is overwritten with the TR byte
which is input from the transmit trail trace controller.
The first byte in the fourth row of the frame is overwritten with the MA byte (see
Figure
10-18), which consists of the
RDI bit, REI bit, payload type, multiframe indicator, and timing source indicator.
The RDI bit can be generated automatically, set to one, or set to zero. The RDI source is programmable
(automatic, 1, or 0). If the RDI is generated automatically, it is set to one when one or more of the indicated alarm
conditions is present, and set to zero when all of the indicated alarm conditions are absent. Automatically setting
RDI on LOS, LOF, or AIS is individually programmable (on or off).
The REI bit can be generated automatically or inserted from a register bit. The REI source is programmable
(automatic or register). If REI is generated automatically, it is one when at least one parity error has been detected
during the previous frame.
The payload type is sourced from a register. The three register bits are inserted in the third, fourth, and fifth bits of
the MA byte in each frame.
The multiframe indicator and timing marker bits can be directly inserted from a 3-bit register or generated from a 4-
bit register. The multiframe indicator and timing marker insertion type is programmable (direct or generated). When
the multiframe indicator and timing marker bits are directly inserted, the three register bits are inserted in the last
three bits of the MA byte in each frame. When the multiframe indicator and timing marker bits are generated, the
four timing source indicator bits are transferred in a four-frame multiframe, MSB first. The multiframe indicator bits
(sixth and seventh bits of the MA byte) identify the phase of the multiframe (00, 01, 10, or 11), and the timing
marker bit (eighth bit of the MA byte) contains the corresponding timing source indicator bit (TMABR register bits
TTI3, TTI2, TTI1, or TTI0 respectively). Note: The initial phase of the multiframe is arbitrarily chosen.
The first byte in the fifth row of the frame is overwritten with the NR byte which can be sourced from a register, from
the transmit FEAC controller, or from the transmit HDLC controller. The NR byte source is programmable (register,
FEAC, or HDLC). Note: The HDLC controller will source eight bits per frame period regardless of whether the NR
byte only, GC byte only, or both are programmed to be sourced from the HDLC controller.
The first byte in the sixth row of the frame is overwritten with the GC byte which can be sourced from a register or
from the transmit HDLC controller. The GC byte source is programmable (register or HDLC).
Once all of the E3 overhead bytes have been overwritten, the data stream is passed on to error insertion. If frame
generation is disabled, the incoming E3 signal is passed on directly to error insertion. Frame generation is
programmable (on or off).
10.6.8.3 Transmit G.832 E3 Error Insertion
Error insertion inserts various types of errors into the different E3 overhead bytes. The types of errors that can be
inserted are framing errors, BIP-8 parity errors, and Remote Error Indication (REI) errors.
The type of framing error(s) inserted is programmable (errored frame alignment bit or errored frame alignment
word). A frame alignment bit error is a single bit error in the frame alignment word (FA1 or FA2). A frame alignment
word error is an error in all sixteen bits of the frame alignment word (the values 09h and D7h are inserted in the
FA1 and FA2 bytes respectively). Framing error(s) can be inserted one error at a time, or four consecutive frames.
The framing error insertion mode (single or four) is programmable.
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