Stream input allows data samples to be written directly from the input stream to one of the Input Vector Registers without the requirement for a ping-pong window buffer. As a result, the memory requirements and latency are reduced.
To maximize the throughput, FIRs can be configured with two input stream ports. Although this might not improve performance if the throughput is limited by other factors, i.e., the output stream bandwidth or the vector processor.
Set TP_DUAL_IP to 1, to create a FIR instance with two input stream ports.
In such a case, the input data will be merged from the two ports in 128 bit chunks, onto one data stream internally, e.g.:
- samples 0-3 to be received on an input stream 0 for cint16 data type,
- samples 4-7 to be received on an input stream 1 for cint16 data type.
Note
For the single rate asymmetric option, dual input streams offer no throughput gain if a single output stream is used. Therefore, dual input streams are only supported with two output streams.