RELEASED
PM4354 COMET-QUAD
DATASHEET
PMC-1990315
ISSUE 6
FOUR CHANNEL COMBINED E1/T1/J1
TRANSCEIVER / FRAMER
8
PIN DESCRIPTION
By convention, where a bus of four pins is present, the index indicates to which quadrant the pin
applies. With BRCLK[1:4], for example, BRCLK[1] applies to quadrant #1, BRCLK[2] applies to
quadrant #2, BRCLK[3] applies to quadrant #3, and BRCLK[4] applies to quadrant #4.
Pin Name Type Pin No. Function
T1 and E1 System Side Serial Clock and Data Interface
BRCLK[1] I/O
BRCLK[2]
BRCLK[3]
BRCLK[4]
E2 Backplane Receive Clocks (BRCLK[1:4]). The Backplane Receive Clock,
F16 BRCLK[x], is used to update BRPCM[x] and BRSIG[x] and to either update or
N1 sample BRFP[x], depending on the direction of BRFP[x]. The active edge of
N16 BRCLK[x] for sampling/updating BRPCM[x], BRSIG[x], and BRFP[x] is
configurable.
In Receive Clock Master Mode, BRCLK[x] is configured as an output and can
be either a 1.544 MHz or 2.048 MHz clock derived from the recovered line
rate timing, with optional jitter attenuation.
When in Receive Clock Master: Nx64Kbit/s mode, BRCLK[x] is gapped
during the framing bit position (T1 mode only) and optionally for between 1
and 24 DS0 channels or 1 and 32 timeslots in the associated BRPCM[x]
stream.
When in Receive Clock Slave: Full T1/E1 mode, BRCLK[x] is configured as
an input and is either a 1.544MHz clock in T1 mode or a 2.048MHz clock in
T1 or E1 modes. BRCLK[x] is a nominal 1.544 or 2.048 MHz clock +/-
50ppm with a 50% duty cycle.
When in Receive Clock Slave: H-MVIP mode, BRCLK[x] is configured as an
input and is unused. In this mode, it is recommended that BRCLK[x] be
connected via an external resistor to ground.
After a reset, BRCLK[x] is configured as an input.
BRSIG[1]
BRSIG[2]
BRSIG[3]
BRSIG[4]
Output E3
G15
P2
P16
Backplane Receive Signaling (BRSIG[1:4]). Each BRSIG[x] contains the
extracted channel associated signaling bits for each channel in the frame,
repeated for the entire superframe. Each channel's associated signaling bits
are valid in bit locations 5,6,7,8 of the channel and are channel-aligned with
the BRPCM[x] data stream.
When in Receive Clock Slave: H-MVIP mode, BRSIG[x] is unused and driven
low.
BRSIG[x] is updated on the active edge of BRCLK[x].
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC. AND FOR ITS CUSTOMERS’ INTERNAL USE
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