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Author Topic: shift register 74HC595 goes crazy on bootup  (Read 407 times)
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Hi,

I just learned how to control many LEDs with help of chained 74HC595 swtich registers. However, on bootup of the arduino all LEDs are uncontrollable lit. Somewhere else someone mentioned that a pull down resistor would help. Is this the solution? If yes how would I integrate such a resitor?

Many thanks!
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Is this the solution?

No - a pull up resistor

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If yes how would I integrate such a resitor?

From the output enable pin (pin13) to +5V about 3K3. Then connect this pin to the arduino and set it low when you want the outputs to be active.
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