controlling existing LEDs on a pcb - Raspberry Pi Forums

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i want reuse leds on old modem. problem following:
+ on leds shared on line. ground individual leds.
if other way around connect each individual + on leds gpio-pins on pi , wire 1 of grounds ground on pi.
have idea how can solve this? connect each led indivdual gpio + ground i'd activate other leds shortened together.

connect + 3.3v, connect - of each led gpio via suitable resistor. when gpio high (on/1) led off. when gpio low (off/0) led on.

have reverse logic in program turn gpio off turn led on.


raspberrypi



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