Time Division Demultiplexer - 2020.2 English

Vivado Design Suite Reference Guide: Model-Based DSP Design Using System Generator (UG958)

Document ID
Release Date
2020.2 English

This block is listed in the following Xilinx® Blockset libraries: Basic Elements, and Index.

The Xilinx Time Division Demultiplexer block accepts input serially and presents it to multiple outputs at a slower rate.

Block Interface

The block has one data input port and a user-configurable number of data outputs, ranging from 1 to 32. The data output ports have the same arithmetic type and precision as the input data port. The time division demultiplexer block also has optional input-valid port (vin) and output-valid port (vout). Both the valid ports are of type Bool.

For single channel implementation, the time division demultiplexer block has one data input and output port. Optional data valid input and output ports are also allowed. The length of the frame sampling pattern establishes the length of the input data frame. The position of 1 indicates the input value to be downsampled and the number of 1's correspond to the downsampling factor. The behavior of the demultiplexer block in single channel mode can best be illustrated with the help of the figure below. Based on the frame sampling pattern entered, the first and second input values of every input data frame are sampled and presented to the output at the rate of 2.

Figure 1. Single Channel Implementation

For single channel implementation, the number of values to be sampled from a data frame should evenly divide the size of the input frame. Every input data frame value can also be qualified by using the optional valid port.

Block Parameters

The block parameters dialog box can be invoked by double-clicking the icon in your Simulink® model.

Parameters specific to this block are as follows.
Frame sampling pattern
Specifies the size of the serial input data frame. The frame sampling pattern must be a MATLAB® vector containing only 1's and 0's.
Specifies the demultiplexer behavior to be either in single or multiple channel mode. The behaviors of these modes are explained above.
Provide Valid Port
When selected, the demultiplexer has optional input and output valid ports (vin / vout). The vin port allows to qualify every input data value as part of the serial input data frame. The vout port marks the state of the output ports as valid or not.

Parameters used by this block are explained in the topic Common Options in Block Parameter Dialog Boxes.