This is the JEDEC and Source for both a Dual 7-Segment Hexadecimal and a Single 7-Segment Hexadecimal Display Driver using GAL22V10 and GAL16V8 PLDs. The driver uses a clocked input to multiplex the displays, so that one display is lit when the clock is high, and the other when the clock is low. With a fast enough clock speed the two displays both appear to be displayed at the same time.
The code is written for WinCUPL. See the Instructables page for more details.
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