DS3112
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Signal Name:
Signal Description:
Signal Type:
These output signals present the demultiplexed serial clocks from one of the 28 T1 data streams or from
one of the 16/21 E1 data streams (Section 7.4). The T1 or E1 serial data streams at the associated LRDAT
signals can be clocked out of the device either on rising edges (normal clock mode) or falling edges
(inverted clock mode) of LRCLK. This option is controlled via the LRCLKI control bit in Master Control
Register 2 (Section 4.2). When the M13/E13 multiplexer is disabled, then these outputs are meaningless
and should be ignored.
Signal Name:
LRCCLK
Signal Description:
Low Speed (T1 or E1) Receive Common Clock Input
Signal Type:
Input
If enabled via the LRCCEN control bit in Master Control Register 1 (Section 4.2), all 28 LRCLK or
16/21 LRCLK can be slaved to this common clock input. In T3 mode, LRCCLK would be a 1.544MHz
clock and in E3 mode, LRCCLK would be 2.048MHz. Use of this configuration is only possible in
applications where it can be guaranteed that all of the multiplexed T1 or E1 signals at the far end are
based on a common clock. If this signal is not used, then it should be tied low. This signal can be
internally inverted. This option is controlled via the LRCLKI control bit in Master Control Register 2
(Section 4.2).
2.6 LOW SPEED (T1 OR E1) TRANSMIT PORT SIGNAL DESCRIPTION
Signal Name:
LTDAT1 to LTDAT28
Signal Description:
Low Speed (T1 or E1) Transmit Serial Data Inputs
Signal Type:
Input
These input signals sample the serial data from the 28 T1 data streams or the 16/21 E1 data streams that
will be multiplexed into a single T3 or E3 data stream. Data can be clocked into the device either on
falling edges (normal clock mode) or rising edges (inverted clock mode) of the associated LTCLK. This
option is controlled via the LTCLKI control bit in Master Control Register 2 (Section 4.2). Also, the data
can be internally inverted before being multiplexed if enabled via the LTDATI control bit in Master
Control Register 2 (Section 4.2). When the device is in the E3 Mode, LTDAT17 to LTDAT28 are
ignored and should be tied low. When the device is in the G.747 Mode, LTDAT4, LTDAT8, LTDAT12,
LTDAT16, LTDAT20, LTDAT24, and LTDAT28 are ignored and should be tied low. When the
M13/E13 multiplexer is disabled, then these inputs are ignored and should be tied low.
Signal Name:
LTCLK1 to LTCLK28
Signal Description:
Low Speed (T1 or E1) Transmit Serial Clock Inputs
Signal Type:
Input
These input signals clock data in from the 28 T1 data streams or from the 16/21 E1 data streams. The T1
or E1 serial data streams at the associated LTDAT signals can be clocked into the device either on falling
edges (normal clock mode) or rising edges (inverted clock mode) of LTCLK. This option is controlled via
the LTCLKI control bit in Master Control Register 2 (Section 4.2). When the device is in the E3 Mode,
LTCLK17 to LTCLK28 are meaningless and should be tied low. When the device is in the G.747 Mode,
LTCLK4, LTCLK8, LTCLK12, LTCLK16, LTCLK20, LTCLK24, and LTCLK28 are meaningless and
should be tied low. When the M13/E13 multiplexer is disabled, then these inputs are ignored and should
be tied low.
LRCLKA/LRCLKB
Low Speed (T1 or E1) Receive Drop Port Serial Clock Outputs
Output