FWIW, my initial thought here was not transistor-transistor logic but through-the-lens (re: camera light metering). I was excited to learn that maybe someone ha

FWIW, my initial thought here was not transistor-transistor logic but through-the-lens (re: camera light metering). I was excited to learn that maybe someone had waded through the stovepiped mess of TTL metering across camera manufacturers and developed an open-source solution.