FPGAs (#315)

mesecons_fpga/doc/fpga/description.html

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+FPGAs can be used to chain multiple logic gates together in a compact manner.
+They come with 4 I/O ports and 10 internal registers,
+which can then be connected with eachother to form logic circuits.<br />
+Supported gate types: <b>AND</b>, <b>OR</b>, <b>NOT</b>, <b>XOR</b>, <b>NAND</b>, <b>XNOR</b>, <b>Buffer</b> (=)<br />
+I/O ports: <b>A B C D</b>; Registers: numbered <b>0</b> to <b>9</b>