184.108.40.206. Changing Block Size
To change the size of the FFT on a block-by-block basis, change the value of the fftpts simultaneously with the application of the sink_sop pulse (concurrent with the first input data sample of the block).
fftpts uses a binary representation of the size of the transform, therefore for a block with maximum transfer size of 1,024.
Always drive fftpts_in even if you are not dynamically changing the block size. For a fixed implementation drive it to match the transform length in the parameter editor.