Dynamic point size is selected using TP_DYN_PT_SIZE = 1. When set, the library unit has two input ports and two output ports. There is a header input port
and a data input port. Similarly there is an output header port and an output data port.
The header for both input and output is a fixed size of 256bits considered as 8 fields each of int32 type.
The fields hold the following information:
| Field index | Description |
|---|---|
| 0 | Direction. Set this to 0 for inverse FFT and 1 for forward FFT |
| 1 | Not used |
| 2 | N, where the point size is 2^N * 3^P * 5^Q |
| 3 | P, where the point size is 2^N * 3^P * 5^Q |
| 4 | Q, where the point size is 2^N * 3^P * 5^Q |
| 5 | Not used |
| 6 | Not used |
| 7 | Error flag (set on output if the pointsize is invalid) |