VFD Display Counter Test (Arduino)

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Upcycled VFD Display Counter Test (Arduino)

(YouTube video) 

All parts are recycled or recovered from obsolete electronics, with the exception of the Arduino board. 

The VFD is being driven by 2 ULN2308 transistor arrays via 10K pull-up resistors to 12volts. There are a total of 16 lines, 6 for digits and 10 for segments. Normally the VFD elements are held high (ON) , but switching a ULN2308 transistor ON pulls the line to GND and turns the VFD segment (or digit) OFF, so inverted logic. 

The 2volts for the VFD filament is coming from the Arduino 5volt line via a 10R resistor.

The code is based on the Arduino SevenSeg library but I will be writing my own code with interrupt-driven multiplexing for the VFD digits.

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