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RELEASED
PM4354 COMET-QUAD
DATASHEET
PMC-1990315
ISSUE 6
FOUR CHANNEL COMBINED E1/T1/J1
TRANSCEIVER / FRAMER
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC. AND FOR ITS CUSTOMERS’ INTERNAL USE
54
BRCLK[x] may optionally be configured as clock master. This is represented with the above figure
but with BRCLK[x] being driven by the COMET-QUAD rather than being an input.
When CCS H-MVIP is enabled, BRCLK[1:4] must be configured to run at 2.048 MHz.
9.19 Backplane Transmit System Interface (BTIF)
The Backplane Transmit System Interface (BTIF) block provides system side serial clock and data
access as well as H-MVIP access for up to 4 T1 or E1 transmit streams. There are several master
and slave clocking modes for serial clock and data system side access to the T1 and E1 streams.
When enabled for 8.192 Mbit/s H-MVIP there are three separate signals for data and signaling.
Information on programming the Backplane Transmit System Interface for various modes can be
found in the Operation section.
Three Clock Master modes provide a serial clock and data backplane transmit interface with per
link clocking provided by COMET-QUAD: Clock Master: Full T1/E1, Clock Master: Nx64Kbit/s and
Clock Master: Clear Channel. Four Clock slave modes provide two serial clock and data
backplane transmit modes, a mixed clock-and-data/H-MVIP mode, and a pure H-MVIP mode all
with externally sourced clocking: Clock Slave: Full T1/E1, Clock Slave: Full T1/E1 with CCS H-
MVIP, Clock Slave: Clear Channel and Clock Slave: H-MVIP.
In Clock Master modes the transmit clock can be sourced from either the common transmit clock,
CTCLK, the received clock for that link, or one of the two recovered clocks.
Figure 15:
- Transmit Clock Master: Full T1/E1
T1-XBAS/E1-TRAN
BasicTransmitter:
Frame Generation,
Alarm Insertion,
Signaling Insertion,
Trunk Conditioning
Line Coding
TRANSMITTER
BTPCM[1:4]
BTSIG[1:4]
CTCLK
TJAT
Digital PLL
BTPCM[x], BTSIG[x],
BTP[x]Timed to
BTCLK[x]
Receive CLK[1:4]
Transmit Data[1:4]
Transmit CLK[1:4]
BTFP[1:4]
BTCLK[1:4]
BTIF
Backplane
Transmit
System
Interface
In Transmit Clock Master: Full T1/E1 mode, the backplane transmit clock (BTCLK[x]) is a jitter
attenuated version of the 1.544 MHz or 2.048 MHz receive clock. BTCLK[x] is pulsed for each bit
in the 193 bit T1 frame or for each bit in the 256 bit E1 frame. The backplane transmit data is
sampled from BTPCM[x], the backplane transmit signaling is sampled from BRSIG[x], and the
backplane transmit frame alignment is indicated by BTFP[x].