It is possible to modify the demonstration test bench to drive the core inputs with different data or to perform different operations.
All operations performed by the demonstration test bench to drive the core inputs are done in the stimuli process. This process also contains procedures to simplify driving input data. The drive_data procedure drives one or more input data samples with the specified data, controlling AXI4 signals to adhere to the AXI4 protocol and keep to the configured input sample rate of the core. The drive_impulse procedure drives an impulse input, with enough zero-valued samples to allow time for the impulse response to emerge on the output data channel of the core. To drive input data other than an impulse, either use the drive_data procedure repeatedly with specific input data values, or copy and modify the drive_impulse procedure.
The stimuli process is comprehensively commented, to explain clearly what is being done. New data, configuration and reload operations can be added by copying and modifying sections of this process.
The clock frequency of the core can be modified by changing the CLOCK_PERIOD constant.