MT9076 Datasheet, PDF (13/160 Pages) Mitel Networks Corporation – T1/E1/J1 3.3V Single Chip Transceiver

Preliminary Information
Framing Algorithm
T1/J1 Mode
• Synchronizes with D4 or ESF protocols
• Supports SLC-96 framing
• Framing circuit is off-line
• Transparent transmit and receive modes
• In D4 mode the Fs bits can optionally be
cross checked with the Ft bits
• The start of the ESF multiframe can be
determined by the following methods:
• Free-run
• Software reset
• Synchronized to the incoming multiframe
• An automatic reframe is initiated if the
framing bit error density exceeds the
programmed threshold
• In transparent mode, no reframing is forced
by the device
• Software can force a reframe at any time
• In ESF mode the CRC-6 bits can be
optionally confirmed before forcing a new
frame alignment
• During a reframe the signaling bits are frozen
and error counting for Ft, Fs, ESF framing
pattern and CRC-6 bits is suspended
• If J1 CRC-6 is selected the Fs bits are
included in the CRC-6 calculation
• J1 CRC-6 and J1 Yellow Alarm can be
independently selected
• Supports robbed bit signaling
Line Coding
T1/J1 Mode
• B8ZS or AMI line coding
• Pulse density enforcement
• Forced ones insertion
MT9076
E1 Mode
• MT9076 contains 3 distinct and independent
framing algorithms
1. Basic frame alignment
2. Signaling multiframe alignment
3. CRC-4 multiframe alignment
• Transparent transmit and receive modes
• Automatic interworking between interfaces
with and without CRC-4 processing
capabilities is supported
• An automatic reframe is forced if 3
consecutive frame alignment patterns or
three consecutive non-frame alignment bits
are received in error
• In transparent mode, no reframing is forced
by the device
• Software can force a reframe at any time
• Software can force a multiframe reframe at
any time
• E-bits can optionally be set to zero until CRC
synchronization is achieved
• Optional automatic RAI
• Supports CAS multiframing
• Optional automatic Y-bit to indicate CAS
multiframe alignment
E1 Mode
• HDB3 or AMI line coding
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