Adafruit .56" display

Adafruit 0.56" 4-digit 7-segment Display W/Backpack

Hi all
I bought this display around 4 years ago and have it working in an Arduino program. It works great!
I am making a couple more of my machines and I bought the same display, but it doesn't work with my program anymore. (I bought two more displays thinking something is wrong with dispay, but all three don't work) Can someone walk me through loading a test program up on the UNO with just the display to see if it will work with the test program? Is there a test program already on the Arduino UNO?
Thank you for any help your can give me.

The adafruit backpack library has lots of examples (File->examples->Adafruit LED Backpack Library->...) . These are i2c devices so you can also run the i2c bus scanner example to see if it is properly detected (File->examples->Wire->i2c_scanner)

step one:
start an i2c scanner (Examples / Wire / i2c_scanner) and check if you get response and which I2C address is used by the new displays in contrast to the old Adafruit display.

Thanks noiasca
can you give me a step by step with where to make my connections?

Adafruit has a step by step description:
https://learn.adafruit.com/adafruit-led-backpack/0-dot-56-seven-segment-backpack

please answer precisely:
a) does the "old" display work with todays program of the library called "sevenseg"?
b) does the "new" display work with todays program?
if you have to answer one ore more questions with no:
c) provide a link of what "old" display you have bought
d) provie a link of the "new" display you have bought
e) provide a link of the Arduino you have bought/you are using
f) show good pictures of your wiring of the "new" display to the Arduino. We must be able to see EACH single wire how it is connected from the display to the Arduino.
g) try the I2C Scanner as adviced already in answer #4 and copy the result of the I2C Scanner Sketch to the forum.

We might be able to help if you provide the necessary information from a - g.

I can't answer the question about the old display, if it works with todays program. It is running in the machine I built a few years ago in an archery shop. I can give you a picture of where I bought it....

the new display was bought here.... Adafruit 0.56" 4-digit 7-segment Display W/Backpack | eBay

The Arduino is an UNO
I can't get the new display to work, I've connected the C to A5 and D to A4 and power to 5v and ground to grd.

Where can I buy a new display with the backpack already soldered on and I only have to connect the wires? and verified it works. I will pay someone to do this for me and send it.

Here is a link to the machine I built......... Archery string making and serving

Anyone?

You can purchase one directly from Adafruit: Adafruit 0.56 4-Digit 7-Segment Display w/I2C Backpack - Green : ID 880 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits

Have you run the i2c scanner program? What did it report? Did you read the tutorial from reply #6. I'm not sure what you want folks to be doing for you. You have been given several suggestions for how to debug/troubleshoot this.

You can purchase one directly from Adafruit: Adafruit 0.56 4-Digit 7-Segment Display w/I2C Backpack - Green : ID 880 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits
I did this last night and bought 4 of them.

Have you run the i2c scanner program?
If you are talking about the link to the Adafruit site....yes I tried that and it don't work, nothing lights up. I've tried it on all three displays I bought.

Yes I read the tutorial.

> I can't find the person that wrote the program for me anymore. Does anyone know where to find someone to hire to help me with this problem?

You have been given several suggestions for how to debug/troubleshoot this.
The suggestion you gave me, I sent you a message and said I don't know how to do this. What is an i2c device? what is a bus scanner? Where do I hook the connections to the UNO? There is C, D, + and - on the backpack.
The link on the adafruit website was very detailed and easy to follow, and they still don't work. I guess I'll just wait for my new displays to come in the mail and try again.

Your first suggestion didn't tell me where to connect the 4 leads to the Arduino UNO
I connected them to A4 and A5 and 5v and grd (C to A5 and D to A4)
It didn't work, but I'm not sure those connection are where they go. That's what I was waiting for was those instructions.
I'm guessing these displays are bad and I will just wait for the new ones I bought from Adafruit.
I will see if I can return these 3 to the EBay seller.

This is described here:
https://learn.adafruit.com/adafruit-led-backpack/0-dot-56-seven-segment-backpack-arduino-setup

  • Connect CLK to the I2C clock - on Arduino UNO thats Analog #5,
  • Connect DAT to the I2C data - on Arduino UNO thats Analog #4,
  • Connect GND to common ground
  • Connect VCC+ to power 5V

make real pictures of your UNO - the Module and the wiring. We must be able to idenfy each single wire.

Than go to your Arduino IDE

FILE
EXAMPLES
WIRE
i2c_scanner

load this sketch to your Arduino, and copy paste the result from the serial monitor to the forum

Library

gfx

BusIO

done

And.... what was the output of running the i2c_scanner sketch? Upload it and then open the Serial Monitor and see what devices are "found" on the bus.

serial monitor

you can mark output of the serial monitor with the mouse and copy - paste the text from serial monitor to the forum. No need for a picture with text only.

The output of the i2c Scanner shows that your device has I2C address 0x74

Now read this page of the adafruit guide
https://learn.adafruit.com/adafruit-led-backpack/changing-i2c-address

don't change anything on your hardware. Only read what adafruit has written.

Go to the sketch sevenseg.ino
around row 34 you find a different address in the example sketch.
change this to 0x74

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Please learn how to copy-paste code to code windows.
Please learn how to copy-paste output from the Serial Terminal to your message.

I possess a similar 0.56 HT16K33 display. So I installed libraries and ran examples on a Uno

Using library Wire at version 1.0 in folder: C:\Program Files\Arduino-1.8.13\hardware\arduino\avr\libraries\Wire 
Using library Adafruit_GFX_Library at version 1.10.11 in folder: C:\Users\David\Documents\Arduino\libraries\Adafruit_GFX_Library 
Using library Adafruit_LED_Backpack_Library at version 1.3.1 in folder: C:\Users\David\Documents\Arduino\libraries\Adafruit_LED_Backpack_Library 
Using library Adafruit_BusIO at version 1.3.2 in folder: C:\Users\David\Documents\Arduino\libraries\Adafruit_BusIO 
Using library SPI at version 1.0 in folder: C:\Program Files\Arduino-1.8.13\hardware\arduino\avr\libraries\SPI 
"C:\\Users\\David\\AppData\\Local\\Arduino15\\packages\\arduino\\tools\\avr-gcc\\7.3.0-atmel3.6.1-arduino7/bin/avr-size" -A "C:\\Users\\David\\AppData\\Local\\Temp\\arduino_build_695337/sevenseg.ino.elf"
Sketch uses 7448 bytes (23%) of program storage space. Maximum is 32256 bytes.
Global variables use 461 bytes (22%) of dynamic memory, leaving 1587 bytes for local variables. Maximum is 2048 bytes.

Note that enabling verbose compile via File->Preferences means that I can see the full build report.
However the only "useful" lines are the library and memory use e.g. what I pasted above.

My module has A0-A2 unchanged (virgin gold pads). i.e. Slave address is 0x70.
I suspect that you have A2 with solder link.

David.

noiasca
sorry about the picture. I am new to this and I thought you wanted pictures of everything.
Copy and Paste is a basic knowledge that I know very well, I will do that when I can.
Thanks for your help with this. I did get it to work. It is going through different numbers on the display, so it seems to be working.
I will look for the code in my other program and change to .074

Please learn how to copy-paste code to code windows.
Please learn how to copy-paste output from the Serial Terminal to your message.

I don't have to learn to copy-paste, I know how to do that. I was understanding pictures were wanted to help me. Its hard to understand what you guys are asking sometimes.
I am not a programmer, nor do I want to learn, but I can follow simple instructions to change the existing code. I am too old with too many other hobbies. Time is not on my side to be a programmer.
I was not understanding what you guys wanted me to do. After reading the link noiasca pasted, I have a little better understanding of the A0-A3
I really don't understand the code you pasted. But my LED seems to be working now, and I will look for the address in my other program.
Thanks for responding to my help request. I really appreciate it.

No one expects Arduino users to be expert programmers.
But it helps if you can copy-paste links, code, text, ...
Code-windows preserve the text integrity.
And sometimes a photo of your actual wiring is necessary.

It is simple. Pasted text is readable (and copy-pasteable). Screenshots are difficult to read.

Anyway, I am pleased that you have the display working.

A0, A1, A2 gold pads are designed for changing the Slave address.
Which means that you can have up to eight displays in a single project.

David.

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