PM6341 E1XC
DATA SHEET
PMC-910419
ISSUE 8
E1 FRAMER/TRANSCEIVER
Register 05H: E1XCTransmit Backplane Options
Bit
Type
Function
Default
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Unused
Unused
X
X
X
X
0
Unused
Unused
R/W
BTXCLK
Unused
X
0
R/W
R/W
BTX2RAIL
BTXMFP
0
This register allows software to configure the Transmit backplane interface
format.
BTXCLK:
The BTXCLK bit selects the source of the TRAN transmit clock input signal.
When BTXCLK is set to logic 1, the TRAN transmit clock is driven with the
2.048MHz recovered PCM output clock (RCLKO) from the receiver section.
When BTXCLK is set to logic 0, the TRAN transmit clock is driven with the
2.048MHz backplane transmit clock (BTCLK). Note that this bit must be set
to logic 1 when Line Loopback is enabled.
BTX2RAIL:
The BTX2RAIL bit selects whether the backplane transmit data signal
presented to the transmitter on the multifunction inputs BTPCM/BTDP and
BTSIG/BTDN are in either dual-rail or single-rail format. When BTX2RAIL is
set to logic 1, the multifunction pins become the BTDP and BTDN dual-rail
inputs, which bypass the TRAN and input directly into the jitter attenuator. It is
expected that the framing bits be already inserted into the dual-rail streams
before they are input on BTDP and BTDN. When BTX2RAIL is set to logic 0,
the multifunction pins become the BTPCM and BTSIG digital inputs.
BTXMFP:
The BTXMFP bit selects the type of backplane frame alignment signal
presented to the transmitter BTFP input. When BTXMFP is set to logic 1,
BTFP must be brought high to mark bit 1 of frame 1 of every 16 frame
signalling multiframe and brought low following bit 1 of frame 1 of every 16
frame CRC multiframe. This mode allows both multiframe alignments to be
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
80
PMC [ PMC-SIERRA, INC ]
