This implements a state machine using a external SPI flash. It has 5 inputs, 6 outputs and 10 internal state bits.
This essentially implements 16x 15 input look up tables stored in external SPI flash. 6 of the LUTs drive general purpose outputs and the remaining 10 are looped back internally as state bits. The inputs to the LUTs are 5 general purpose inputs and the 10 state bits.
The circuit sends out the read command 8'h03 followed by a 24 bit address consisting of {8'h00, [10 state bits], [5 GPI], 1'b0}. The circuit then shifts in 2 bytes to read the LUT values. The first 10 bits shifted in are the state bits and the next 6 drive the outputs.
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