CMSIS-DSP/ComputeGraph/examples/example10

Example 10

Please refer to the simple example to have an overview of how to define a graph and it nodes and how to generate the C++ code for the static scheduler. This document is only explaining additional details

This example is implementing a dynamic / asynchronous mode.

It is enabled in graph.py with:

conf.asynchronous = True

There is an option to increase the FIFO size compared to their synchronous values. To double the value (increase by 100%) we write:

conf.FIFOIncrease = 100

The graph implemented in this example is:

There is a global iteration count corresponding to one execution of the schedule.

The odd source is generating a value only when the count is odd.

The even source is generating a value only when the count is even.

The processing is adding its inputs. If no data is available on an input, 0 is used.

In case of FIFO overflow or underflow, any node will skip its execution.

All nodes are generating or consuming one sample but the FIFOs have a size of 2 because of the 100% increase requested in the configuration settings.

Thus in this example :

• A sample is not always generated on an edge
• A sample is not always available on an edge

The dataflow on each edge is thus not static and vary between iterations of the schedule

Expected outputs

Schedule length = 9
Memory usage 34 bytes

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