This instalment of Elektor Books presents material excerpted from Monte Dalrymple’s book Inside an Open-Source Processor published by Elektor. FPGA technology in combination with (V)HDL is hot among electronicists and RISC-V adds the open-source path to professional applications  In this article, we examine some side-by-side comparisons and results obtained from an example application running on both Lattice and Xilinx FPGA boards of the ‘Alchitry’ series now available from Elektor. But first, a few tips!