An ECP5 SHA3 digest module using freecores/sha3 implementation

This is an SHA3 message digest module for a limited use. Input size should be less than 568-bit. For more large inputs, see the original freecores/sha3 implementation.

The target FPGA is ECP5-85G and yosys/nextpnr-ecp5 open software developing system is assumed. The module is tested successfully on the real chip with 50Mhz clock.

sha3.v includes keccak implementation from freecores/sha3 which is imported as a submodule. Although the original freecores/sha3 gives only 512-bit width digests, other widths can be handled with a few tiny modifications.

Device utilisation

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