Digits not working on 1.2" 7Segment I2C backpack

EL Wire/Tape/Panels, LEDs, pixels and strips, LCDs and TFTs, etc products from Adafruit

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m.lowther
 
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Re: Digits not working on 1.2" 7Segment I2C backpack

Post by m.lowther »

Thank you very much "adafruit_support_bill" for your quick reply and for the help.
I'm pretty sure I'm just overlooking something very simple, but I'm just not aware of what it is exactly.

Below you will find the connections I've made from the 1.2" i2c 7-Segment Display backpack to the Arduino Mega:

DIAGRAM LEGEND: Backpack Pin ID --> Wire Color ---> Arduino Pin # & Location

V_IO = YELLOW = 3.3V &/or 5V (tried both)
+5V = RED = Arduino 5V Header pin (found in power section by caps and dc jack)
GND/- = BLACK = Arduino GND pin (tried the 2 in the power section as well as the one over by AREF)
SDA = GREEN = Arduino SDA 20 pin in Communication section)
SCL = BLUE = Arduino SCL 21 pin in Communication section)

Unit is powered by means of a DC Wall-wart 9V 1A adapter which is connected to the DC power regulator barrel-jack input by the caps on the Arduino.

Thanks again,
Mitchell
Connections to the Arduino Mega from the 1.2in I2C 7-segment Display Backpack
Connections to the Arduino Mega from the 1.2in I2C 7-segment Display Backpack
Mega_Connections.jpg (127.42 KiB) Viewed 305 times

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adafruit_support_bill
 
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Re: Digits not working on 1.2" 7Segment I2C backpack

Post by adafruit_support_bill »

The bus/signal voltage should be 5v, since that is what the Mega uses. Your soldering is fine and your wiring is direct. The only other thing I can suggest is to tug on each connection to make sure it firmly gripped. Sometimes the spring contacts get bent or stretched out and don't make good contact. If you don't see any signs of life still, contact [email protected] with a link to this thread and we can send you out a replacement.

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m.lowther
 
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Re: Digits not working on 1.2" 7Segment I2C backpack

Post by m.lowther »

Thanks... I'll try different wire types and retry the 5V for the bus/signal.
I appreciate the speedy replies on this.

All the best to you,
Mitchell

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m.lowther
 
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Can this auto display non-integer values without fancy logic

Post by m.lowther »

Quick question:

Can the colon in the middle of this display have only the bottom dot illuminated automatically when sending non-integer values to the display via the matrix.print cmd?
For example: printing x.xx to the display or xx.xx? Or is it going to show up as: xxx.x with the dot at the top or as xx:xx?
I can't tell because mine doesn't work as it looks like the backpack most likely is doa. The tutorial seems to suggest the left-most colon can be controlled manually that way, but says nothing about the middle one.

This display was to be used in a project for stats display. The period is definitely needed. I was originally planning to buy the smaller backpack display until I saw that it was available in the insanely large 1.2" segments. I didn't notice that this appears to be more geared to being a clock interface. If I can't get that to work, I'll need to get the smaller product instead when I ask for a replacement. Anyhow, any info you can share would be appreciated as I need to get a replacement quickly. My deadline for this was next Monday.

Thanks,
M

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adafruit_support_bill
 
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Re: Digits not working on 1.2" 7Segment I2C backpack

Post by adafruit_support_bill »

Both dots of the center colon are connected to the same pin. See page 3 of the data sheet:
http://www.adafruit.com/datasheets/BL-Q120A-41.pdf

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