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STANDARD PRODUCT
PMC-Sierra, Inc.
PM6344 EQUAD
PMC-951013
ISSUE 5
QUADRUPLE E1 FRAMER
68
Register 005H, 085H, 105H, 185H: Transmit Backplane Options
Bit
Type
Function
Default
Bit 7
Unused
X
Bit 6
Unused
X
Bit 5
R/W
BTFPREF
0
Bit 4
Unused
X
Bit 3
R/W
BTXCLK
0
Bit 2
Unused
X
Bit 1
R/W
BTX2RAIL
0
Bit 0
R/W
BTXMFP
0
This register allows software to configure the Transmit backplane interface
format.
BTFPREF:
The BTFPREF bit selects the source of the input frame pulse. When
BTFPREF is set to logic 1, BTFP[1] is used as the input transmit frame pulse
for the associated interface. If BTFPREF is set to logic 0, BTFP[4:1] are used
as the input transmit frame pulses for the associated interface. Note that
when BTFPREF is set to a logic 1, the corresponding BTCLK[x] must be
phase aligned to BTCLK[1] to ensure proper sampling of BTFP[1].
The BTFPREF bit in register 005H has no effect if MENB is a logic 0. In this
case, MTFP is used to generate internal frame pulses for each quadrant.
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[x]) 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[x]).
BTX2RAIL:
The BTX2RAIL bit selects whether the backplane transmit data signal
presented to the transmitter on the multifunction inputs BTPCM/BTDP[x] and
BTSIG/BTDN[x] are in either dual-rail or single-rail format. When BTX2RAIL
is set to logic 1, the multifunction pins become the BTDP[x] and BTDN[x]