Instruction Manual

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
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12 FUNCTIONAL TIMING
12.1 Functional Serial I/O Timing
The Serial Interface provides flexible timing to interconnect with a wide variety of serial interfaces. TDEN is an
input signal that can be used to enable or block the TSERO data. The “shaded bits” are not clocked by the
DS33R11. The TDEN must occur one bit before the effected bit in the TSERO stream. Note that polarity of the
TDEN is selectable through LI.TSLCR. In the figure below, TDEN is active low, allowing the bits to clock and
inactive high, causing the next data bit not be clocked. TCLKE can be gapped as shown in the following figure.
Similarly, the receiver function is governed by RCLKI, RDEN and RSERI. RSERI data will not be provided to the
receiver for the bits blocked when RDEN is inactive. The RDEN polarity can be programmed by
LI.RSLCR. The
RDEN signal must be coincident with the RSERI bit that needs to be blocked.
Figure 12-1. Tx Serial Interface Functional Timing
TCLK
gapped
TSER
TCLKE
TDEN
TSERO
TCLKE Gapped
TSERO
Figure 12-2. Rx Serial Interface Functional Timing
TSER
RCLKI
RDEN
RSERI
RCLKI Gapped
RSERI