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1.2'' 7-segment LED HT16K33 Backpack not working
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1.2'' 7-segment LED HT16K33 Backpack not working

by Gpoit on Wed Aug 04, 2021 1:30 pm

Hi,

I have buy one 1.2'' 7-segment LED HT16K33 Backpack and it don't seems to work. I have install both library (Adafruit LED Backpack and Adafruit GFX). I have solder the display according with your instruction. The display is always black. I have try it with an Arduino Uno and a Node MCU 1.0 ESP8266. The wiring was:

Arduino: C to SCL(A3), D to SDA (A4), - to GND, + to 5V and IO to 5V
ESP8266: C to SCL(D1), D to SDA (D2), - to GND, + to Vin (Wich provide 5V when connect to usb) and IO to Vin.

I have also try the i2cdetect librairie to see if it can see the adresses but for both board, it didn't see nothing.

Thanks for your help!

Gpoit
 
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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by adafruit_support_carter on Wed Aug 04, 2021 2:00 pm

Please post a photo of your setup showing all connections. This seems like some kind of connection issue. A photo of your setup will let us take a look for anything obvious.

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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by Gpoit on Wed Aug 04, 2021 3:12 pm

The arduino is currently running the example sevenseg and the console output "7 Segment Backpack Test".

Thanks for your help!
Attachments
20210804_145631.jpg
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Gpoit
 
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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by adafruit_support_carter on Wed Aug 04, 2021 3:31 pm

Thanks. Can you post another one that shows the soldering here more in view:
headers.jpg
headers.jpg (34 KiB) Viewed 80 times


I have also try the i2cdetect librairie to see if it can see the adresses but for both board, it didn't see nothing.

What was this sketch? This is a good initial sanity check since it only requires good connection to the headers pins (in photo above). So want to make sure the sketch actually was something that actually scans as expected.

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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by Gpoit on Wed Aug 04, 2021 3:50 pm

The i2cdetect library will print all the adresse that the arduino can see in the serial monitor.
https://www.arduino.cc/reference/en/lib ... i2cdetect/

I have look for short with my multimeter and there is no short between those pin.
Attachments
20210804_153342.jpg
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Gpoit
 
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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by adafruit_support_carter on Wed Aug 04, 2021 4:44 pm

Thanks. That soldering looks fine.

Can you try the scanner again with this sketch:
https://playground.arduino.cc/Main/I2cScanner/
just to make sure that one also reports back no address found. That i2cdetecet library is probably fine, but just want to make sure we are comparing the same thing.

I just tested this on an UNO to make sure it'd work, and it does report back the expected 0x70 address.
Screenshot from 2021-08-04 13-35-52.png
Screenshot from 2021-08-04 13-35-52.png (49.68 KiB) Viewed 78 times


Also, double check your wires. Maybe try all different wires in case there is a bad one in the set and even a new location on the breadboard.

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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by Gpoit on Thu Aug 05, 2021 7:56 am

I don't know what to say. I let the screen over night. This morning I have try to see if the screen was detected with the sketch that you send me and it return the same thing as you. I have the i2cdetect sketch and it see the display. I have re-upload the sevenseg example and now it work with the ESP8266 and the Arduino UNO. I didn't even have remake the wires, i just place the screen at the same place that it was before.

I don't know what was the problem but now it work!

Thanks for your help!
Attachments
20210805_073912.jpg
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Re: 1.2'' 7-segment LED HT16K33 Backpack not working

by adafruit_support_carter on Thu Aug 05, 2021 1:44 pm

Weird. It could still be a marginal connection issue somewhere? If it acts up again, continue investigating something along those lines. But hopefully it will just work now :)

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Please be positive and constructive with your questions and comments.