DS26556_07 Datasheet, PDF (252/368 Pages) Maxim Integrated Products – 4-Port Cell/Packet Over T1/E1/J1 Transceiver

DS26556 4-Port Cell/Packet Over T1/E1/J1 Transceiver
11.5.17 T1 Transmit Synchronizer
When enabled, the DS26556 transmitter has the ability to identify the D4 or ESF frame boundary within the
incoming NRZ data stream at TSER. The TFM (TCR3.2) control bit determines whether the transmit synchronizer
searches for the D4 or ESF multiframe. Additional control signals for the transmit synchronizer are located in the
TSYNCC register. The Transmit Latched Status 3 (TLS3) register provides a latched status bit (LOFD) to indicate
that a Loss-of-Frame synchronization has occurred, and a real-time bit (LOF) which is set high when the
synchronizer is searching for frame/multiframe alignment. The LOFD bit can be enabled to cause an interrupt
condition on INT.
Note that when the transmit synchronizer is used, the TSYNC signal should be set as an output (TSIO = 1) and the
recovered frame sync pulse will be output on this signal. The recovered multiframe sync pulse will be output if
enabled with TIOCR.0 (TSM = 1).
Register Name:
Register Description:
Address (hex):
TSYNCC
Transmit Synchronizer Control Register
18Eh + (200h x n) : where n = 0 to 3, for Ports 1 to 4
Bit #
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
TSEN SYNCE RESYNC
Default
0
0
0
0
0
0
0
0
Bits 7 to 3: Unused. Must be set = 0 for proper operation.
Bit 2 : Transmit Synchronizer Enable (TSEN)
0 = Transmit Synchronizer Disabled
1 = Transmit Synchronizer Enabled
Bit 1 : Sync Enable (SYNCE)
0 = auto resync enabled
1 = auto resync disabled
Bit 0 : Resynchronize (RESYNC)
When toggled from low to high, a resynchronization of the transmit side framer is initiated. Must be cleared
and set again for a subsequent resync.
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