The basic operation of the FIR is for samples to
enter through the input DATA channel (s_axis_data_t*)
and exit through the output DATA channel (s_axis_data_t*) duly filtered. The output channel optionally supports tready which allows a resource/behavior trade-off. In
circumstances where downstream slave can be guaranteed to accept the maximum bandwidth
of the FIR, tready can be deselected to save resources.
The input DATA channel always supports tready.