An FPGA miner is a type of cryptocurrency mining hardware that uses FPGAs to perform the computational work required to mine cryptocurrencies.

FPGAs are integrated circuits that can be programmed after manufacture to perform specific functions.

Unlike ASICs, which are designed for a specific cryptocurrency algorithm, FPGAs can be reprogrammed to mine different cryptocurrencies or different algorithms.

To program an FPGA crypto miner to mine a specific algorithm, you would need to write code in a Hardware Description Language (HDL) such as Verilog or VHDL.

There are also open-source FPGA development platforms and communities that can provide resources and support for learning HDL programming.