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DS3171/DS3172/DS3173/DS3174
138
0 = Use output clocks for timing reference
1 = Use input clocks for timing reference
Bit 1: Transmit Framer IO Signal Timing Select (TFTS).
This bit controls the timing reference for the signals on
the transmit framer interface IO pins. The pins controlled are TSOFIn, TSERn, and TSOFOn / TDENn. See
for more details.
0 = Use output clocks for timing reference
1 = Use input clocks for timing reference
Bit 0: Transmit Line IO Signal Timing Select (TLTS).
This bit controls the timing reference for the signals on the
transmit line interface IO pins. The pins controlled are TPOSn / TDATn and TNEGn. See
for more
details.
0 = Use output clocks for timing reference
1 = Use input clocks for timing reference
Register Name:
PORT.CR4
Register Description:
Port Control Register 4
Register Address:
(0,2,4,6)46h
Bit
# 15 14 13 12 11 10 9 8
Name
-- -- -- --
RESERVED
LBM2 LBM1 LBM0
Default
0 0 0 0 0 0 0 0
Bit
# 7 6 5 4 3 2 1 0
Name GPIOB3 GPIOB2 GPIOB1 GPIOB0 GPIOA3 GPIOA2 GPIOA1 GPIOA0
Default
0 0 0 0 0 0 0 0
Bits 10 to 8: Loopback Mode [2:0] (LBM[2:0]).
These bits select the loopback modes for analog loopback (ALB),
line loopback (LLB), payload loopback (PLB) and diagnostic loopback (DLB). See
for the loopback
select codes. Default: No Loopback.
Bits 7 to 4: General-Purpose IO B Output Select[3:0] (GPIOB[3:0])
These bits determine which alarm status
signal to output on the GPIO2(port 1), GPIO4(port 2), GPIO6(port 3) or GPIO8(port 4) pins. The GPIO pin must be
enabled by setting the bits in the
registers to output the selected alarm
signal. See
See
for the alarm select codes.
Bits 3 to 0: General-Purpose IO A Output Select[3:0] (GPIOA[3:0])
These bits determine which alarm status
signal to output on the GPIO1(port 1), GPIO3(port 2), GPIO5(port 3) or GPIO7(port 4) pins. The GPIO pin must be
enabled for output by setting the bits in the
register. See
for configuration settings. See
for the alarm select codes.