XRT75R03D_06 Datasheet, PDF (87/135 Pages) Exar Corporation – EXAR DATA SHEET FORMAT TEMPLATES

REV. 1.0.4
BIT NUMBER
1
NAME
STS-1/DS3_n
0
SR/DR_n
XRT75R03D
THREE CHANNEL E3/DS3/STS-1 LINE
TYPE
R/W
R/W
DEFAULT
VALUE
DESCRIPTION
0 STS-1/DS3 Mode Select - Channel_n:
This READ/WRITE bit-field, along with Bit 2 (E3_n) is used
to configure a given channel (within the XRT75R03D) into
either the DS3, E3 or STS-1 Modes.
0 - Configures Channel_n to operate in the DS3 Mode (pro-
vided by Bit 2 [E3_n], within this same register) has been
set to "0").
1 - Configures Channel_n to operate in the STS-1 Mode
(provided that Bit 2 [E3_n], within the same register) has
been set to "0".
NOTE: This bit-field is ignored if Bit 2 (E3_n) has been set to
"1". In this case, Channel_n will be configured to
operate in the E3 Mode.
0 Single-Rail/Dual-Rail Select - Channel_n:
This READ/WRITE bit-field is used to configure Channel_n
to operate in either the Single-Rail or Dual-Rail Mode.
If the user configures the Channel to operate in the Single-
Rail Mode, then all of the following will happen.
• The B3ZS/HDB3 Encoder and Decoder blocks (within
Channel_n) will be enabled.
• The Transmit Section of Channel_n will accept all of the
outbound data (from the System-side Equipment) via the
TPDATA_n (or TxDATA_n) input pin.
• The Receive Section of each channel will output all of the
recovered data (to the System-side Equipment) via the
RPOS_n output pin.
• The corresponding RNEG_n/LCV_n output pin will now
function as the LCV (Line Code Violation or Excessive
Zero Event) indicator output pin for Channel_n.
If the user configures Channel_n to operate in the Dual-Rail
Mode, then all of the following will happen.
• The B3ZS/HDB3 Encoder and Decoder blocks of
Channel_n will be disabled.
• The Transmit Section of Channel_n will be configured to
accept positive-polarity data via the TPDATA_n input pin
and negative-polarity data via the TNDATA_n input pin.
• The Receive Section of Channel_n will pulse the
RPOS_n output pin "High" (for one period of RCLK_n) for
each time a positive-polarity pulse is received via the
RTIP_n/RRING_n input pins. Likewise, the Receive
Section of each channel will also pulse the RNEG_n
output pin "High" (for one period of RCLK_n) for each
time a negative-polarity pulse is received via the RTIP_n/
RRING_n input pins.
0 - Configures Channel_n to operate in the Dual-Rail Mode.
1 - Configures Channel_n to operate in the Single-Rail
Mode.
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