In this video, we test the register we built in the last video (https://youtu.be/CiMaWbz_6E8) and connect it to two more registers like it. After this video, we'll have three registers built and tested: - A register - B register - Instruction register Support me on Patreon: https://www.patreon.com/beneater You can get all the components used in this video from any online electronic components distributor for a few dollars. See https://eater.net/bbcpu8-registers for more. Complete parts list (everything in this video): - Clock circuit from https://youtu.be/SmQ5K7UQPMM - 6x 74LS173 (4-bit D-type register) - 3x 74LS245 (Octal bus transceiver) - 32x LEDs - 22 gauge wire - 5 volt power source (e.g., a USB phone charger)