I have an electromechanical 7-segment clock display with each segment controlled by an electromagnet. A segment is 'on' depending on the polarity of the last pulse to its electromagnet.
Can anyone advise how I could control the electromagnets via the GPIO pins so they turn on/off, as required, once a minute to change the time?
I imagine relays would need to be used. It's complicated because the polarity to each electromagnet needs 'swapping' to turn it on/off.
There are 28 electromagnets in all (7 x 4).