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7-segment 4-digit LED display not working
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7-segment 4-digit LED display not working

by wpeng730 on Wed May 31, 2017 12:51 am

Hi all,

I ordered a red Adafruit 0.56" 4-Digit 7-Segment Display w/I2C Backpack. I soldered the backpack on, connected the pins to my Arduino UNO, powered the display with 3 AA batteries, and ran the sevenseg example program. However, the display refuses to light up at all. I've ordered two of the displays now, and neither work. Could anyone help me get these working? Any assistance is appreciated! Thanks!

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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Wed May 31, 2017 5:45 am

Please post some photos showing your soldering and connections to the display.

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Re: 7-segment 4-digit LED display not working

by wpeng730 on Wed May 31, 2017 4:46 pm

adafruit_support_bill wrote:Please post some photos showing your soldering and connections to the display.


Sure thing, here they are.
Attachments
IMG_20170531_134057.jpg
14-pin
IMG_20170531_134057.jpg (412.71 KiB) Viewed 122 times
IMG_20170531_134050.jpg
4-pin
IMG_20170531_134050.jpg (326.25 KiB) Viewed 122 times

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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Wed May 31, 2017 5:45 pm

The soldering looks excellent. Can you show us your connections to the UNO too?

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Re: 7-segment 4-digit LED display not working

by wpeng730 on Wed May 31, 2017 6:09 pm

adafruit_support_bill wrote:The soldering looks excellent. Can you show us your connections to the UNO too?


Here're the pics.
Attachments
IMG_20170531_150436.jpg
IMG_20170531_150436.jpg (451.6 KiB) Viewed 114 times
IMG_20170531_150428.jpg
IMG_20170531_150428.jpg (404.78 KiB) Viewed 114 times

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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Wed May 31, 2017 6:26 pm

I can't see in your photos, but do you have a common ground connection from the display to the UNO?

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Re: 7-segment 4-digit LED display not working

by wpeng730 on Wed May 31, 2017 6:32 pm

adafruit_support_bill wrote:I can't see in your photos, but do you have a common ground connection from the display to the UNO?


No, I don't believe I do. How would I go about doing that?

wpeng730
 
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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Wed May 31, 2017 6:53 pm

Run a jumper wire from the GND pin of the display backpack to the GND pin of the UNO. Without a common ground reference, the i2c control signals are just floating.

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Re: 7-segment 4-digit LED display not working

by wpeng730 on Wed May 31, 2017 8:27 pm

One of the displays is working now, thanks! I'll probably just assume the one that still doesn't work is broken.

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Re: 7-segment 4-digit LED display not working

by kennburr on Tue Jun 13, 2017 10:52 am

I have an Adafruit .56" 4 digit 7 segment display in which the fourth segment has never worked. All the other digits work just fine. I many many years of professional and personal experience in soldering, and do not believe that the problem is due to poor soldering. Can I send the display back to Adafruit for replacement?

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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Tue Jun 13, 2017 11:13 am

Please post photos showing your soldering to the board.

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Re: 7-segment 4-digit LED display not working

by kennburr on Wed Jun 14, 2017 10:40 pm

see attached picture
Attachments
display7.jpg
display7.jpg (245.67 KiB) Viewed 27 times

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Re: 7-segment 4-digit LED display not working

by adafruit_support_bill on Thu Jun 15, 2017 5:45 am

OK. Please contact support@adafruit.com with a link to this thread for a replacement.

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Please be positive and constructive with your questions and comments.