and -1.5 volts to turn off. His clever solution is to use an Arduino Uno R4 and take advantage of the onboard DAC. To turn on a segment, he connects a segment to a GPIO pin set high while sending ...

What do you do with 144 7-segment displays ... hand-coded lookup tables for each digit. The lookup tables are stored in ROM, saving precious RAM on the Arduino. A clock wouldn’t be any good ...