I have an arduino connected to a 74HC595 shift register, similar to the set-up in this tutorial (http://bildr.org/2011/02/74hc595/
). The output pins of the shift register are connected to some relays. Output pin high sets relay off; output pin low sets relay on.
My problem is that when I start or reset the arduino, the relays chatter rapidly for a second or so. I would like to avoid this.
What is the best way avoid fluctuations in the shift register output pins when the arduino is starting up? I've tried writing to the shift register in the arduino setup() function, but that doesn't seem to be soon enough. I'm using digital output pins 8, 9 and 10 on the arduino to control the shift register. Would I have better luck with different pins?