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I'm new to using the SN74HC595 shift register, and trying to follow this tutorial: https://www.arduino.cc/en/tutorial/ShiftOut based on this configuration:

SN74HC595 IC pinout

When my arduino Uno R3 is plugged in by USB to my Windows-7 x64 PC, it works (in general etc.), but right when I attach pin 16 or pin 10 of the 74HC595 to the 5V pin on the Uno, as it says to do, the entire arduino shuts off and the computer no longer recognizes it, until I disconnect the jumper wire from pin 16 or 13, from the 5v pin on the Uno, then it starts up again

Also just tested, and the same thing happens when I try to connect any of the 74HC595 pins to the 5v Uno pin (after pin 8 of the 74HC595 is connected to the Uno's GND), the whole Uno shuts off and disconnects from the computer

Am I missing something here?

  • 2
    It sounds like you have a short somewhere on the breadboard with the HC595. Could you describe the simplest way to reproduce the problem? – StarCat Jul 8 at 10:23
  • i tried pluggging the pins directly to the ruino pins, only pins 8 and 16, when the register was at diferent points on the breadboard (and the breadboard works with other things too), am I getting the configuration right ? does my register match th kind at the tutorial? – user67332 Jul 8 at 10:27
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    So the problem occurs just connecting the HC595 to its power supply? Did you correctly identify pin 1? – StarCat Jul 8 at 10:29
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    Photos, or it didn't happen. – Majenko Jul 8 at 10:45
  • Sound like there is a short somewhere. But it also sound like you are putting in jumper wires while the Arduino is plugged in. Which you shouldn't do in most cases. Also connecting 5v to any of the 74HC595 pins, while no supplying the power to it's Vcc pin (16) is not great, and can damage both the 595 and possibly the Arduino. – Gerben Jul 8 at 12:51
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when I attach pin 16 or pin 10 of the 74HC595 to the 5V pin on the Uno ... the entire arduino shuts off

This sort of thing usually happens to me when I have made a mistake in the wiring.

This is easy to do as the 595 needs a lot of connections in a small space and it is easy to make a mistake.

In your case it seems you have a wiring mistake that is pulling Vcc low and the ATmega328 IC etc can't run.


I would

  • Re-check the orientation of the 595
  • Re-check each wire paying particular attention to the ground wires, especially the one that pulls 595 OE to ground (it's pin 13 on the 595).
  • If necessary, pull everything off the breadboard and start again with things in a completely different position (turn the IC's round etc) to make me re-think everything.

For fun, I set this up on a Uno clone. I made some mistakes in the wires linking the 595 to the Uno but careful inspection found the problem. I found it easy to mix up the pin-number on the 595 with that on the Uno. Using the same wire colours mentioned in the guide may help.

Here's it working

Uno clone with 595

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