I've had a very time-consuming and frustrating problem where my 8-Bit shift register blinks very fast (10-20 times per second) randomly, sometimes it stops, sometimes it does it slower.
I am using circuits.io to model out my design, and then I build it on my breadboard. My design is this (circuits.io), and it seems to work. You make the sideswitches on the left to connect the wires. The LED represents the state of QO, or output 0. Everything seems fine on the test, but in real life, it does not work at all. I've tried more resistor value (up to 440Ω), and it still flickers. Here's what I'm doing differently in real life than the stimulation:
- I am using the Raspberry Pi as a 5v power source.
- I am not using side switches, rather I am manually placing connector wires down, very inefficient but I don't want to run over to RadioShack and buy some buttons at the moment (They are a bit... overpriced)
Here is the date sheet of 74HC595
Do you think that it is the 74HC595's problem, and I should replace it with another, or I have done my wiring wrong, or I am going crazy? Thanks for any help.
EDIT: I made the circuits.io stimulation look cleaner.