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Got a problem with the Arduino shift out function and a LED array Answered

After looking at this instructable, I wanted to start building my own LED array. I found this Arduino article. I bought the 74HC595N chips and connected everything exactly as the article showed it, and copied the first example program directly into the Arduino. The Arduino is connected through the USB cable to my computer for power.

My problem comes in when I hook the circuit into the 5V on the Arduino. When I hook it up the Arduino shuts itself off. I wasn't sure if it was overloading the Arduino, so I hooked it up to an old, plug in breadboard I have which has a limit of 1.5A. When I hooked up the circuit the breadboard produced a high pitch tone and still nothing happened.

I have checked and rechecked all the connections and jumpers, (even looked at the data sheet for the part) everything seems to check out. The LED's are just simple green LED's, but the resistors I am using are 1k instead of the 220 ohms the article said to use (i had only 1k handy and the LED's still light with a 1k).


Something ain't wired right. It sounds like the breadboard PSU can't cope, so you have a pretty well dead short somewhere.

I figured out what the problem was, I am unfamiliar with the way the breadboard connects the pins, what I thought were small groupings of pins only connected to each other turned out to be rails going down the entire board. Essentially I had 5v hooked directly to ground on the Arduino.

Thanks for your suggestions, if I had a multimeter I would have figured this out awhile ago.

Check over your circuit with a multimeter and make sure there aren't any tiny shorts anywhere.
Did you test the shift registers on a different circuit?  If not, check out this tutorial and try the first circuit to make sure your 595's aren't duds.

Also, try uploading the code from his other led matrix

I can't get his 6x24 code to work, but the code for the 8x10 does work.  Make sure to change the arduino pins to match the new program.

I don't have a working multimeter with me I will have to get one and look for shorts. The circuit i am using is the first Arduino circuit off of the tutorial.

I haven't built Syst3mX's matrix yet, I was planning on building it after I got familiar with the shift registers.

I bought 4 shift registers and have tried three of them, none of them work. Too scared to try the fourth in case I fried the first three. Don't want to have to wait for more parts to ship in.