Port.cr4, Regis – Rainbow Electronics DS3170 User Manual
Page 138
DS3170 DS3/E3 Single-Chip Transceiver
138 of 233
Bit 2: Receive Framer IO Signal Timing Select (RFTS). This bit controls the timing reference for the signals on
the receive framer interface IO pins. The pins controlled are RSER, RSOFO / RDEN. See
for more
details.
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, TSER, and TSOFO / TDEN. 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 TPOS / TDAT and TNEG. 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:
046h
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, pin. The GPIO pin must be enabled by setting the bits in the
and
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 pin. The GPIO pin must be enabled for output by setting the bits in the
for configuration settings. See