STANDARD PRODUCT
PM4351 COMET
DATA SHEET
PMC-1970624
ISSUE 10
COMBINED E1/T1 TRANSCEIVER
COMET is not in a loss of signal state, the RSYNC output is derived from the
recovered receiver clock.
IBCD_IDLE:
When the IBCD_IDLE bit is set to logic 1 gaps the data to the inband code
detector (IBCD) block during the framing bit. This allows the IBCD to be used
to detect an idle code that is inserted only in the payload of the receive DS1
PCM stream. The IBCD must still be programmed to detect the desired
pattern, and otherwise operates unchanged. The IBCD_IDLE bit is only valid
in T1 mode.
TRKEN:
The TRKEN bit enables receive trunk conditioning upon an out-of-frame
condition. If TRKEN is logic 1, the contents of the RX-ELST Idle Code
register are inserted into all time slots (including TS0 and TS16) of BRPCM if
the framer is out-of-basic frame (i.e. the OOF status bit is logic 1). The
TRKEN bit only has effect if RXELSTBYP bit is logic 0. If TRKEN is a logic 0,
receive trunk conditioning can still be performed on a per-timeslot basis via
the RPSC Data Trunk Conditioning and Signaling Trunk Conditioning
registers.
RXMTKC:
The RXMTKC bit allows global trunk conditioning to be applied to the
received data and signaling streams, BRPCM and BRSIG. When RXMTKC is
set to logic 1, the data on BRPCM for each channel is replaced with the data
contained in the data trunk conditioning registers within RPSC; similarly, the
signaling data on BRSIG for each channel is replaced with the data contained
in the signaling trunk conditioning registers. When RXMTKC is set to logic 0,
the data and signaling signals are modified on a per-channel basis in
accordance with the control bits contained in the per-channel control registers
within the RPSC.
E1/T1B:
The E1/T1B bit selects the operating mode of COMET. If E1/T1B is logic 1,
the 2.048 Mbit/s E1 mode is selected. If E1/T1B is logic 0, the 1.544 Mbit/s
T1 mode is selected.
PROPRIETARY AND CONFIDENTIAL
77