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How to set up a 7 segment display on an Arduino ? Answered

 How would i set it up for this display?

on the left side each pin is labeled from top to bottom D0 D1 D2 D3 and Digit on right side Top to bottom +9v+5v and GND (1st Pic) 

The send Pic is just the bottom of the display.

PLZ HELP Thanks!


Thats not a chip number is it ? What's actually written on the package ?

There's a little black box, with 16 legs on it. What does it say on that ?

Give up: Take the LED display off the board, work out the pin out, and connect it to the arduino directly or via a MAX7221.

Much less trouble.


Just the LED part. You need to work out what the common connection to the LEDs is, are they common "cathode" or "anode"

 do i just need the led part or the black chip to? y? THX

I wouldn't bother trying to get them working with that circuit and PCB. 

You can buy simple 7 segment displays at Radio Shack for a couple bucks and you won't have to waste all your time figuring out that circuitry.

There are several ways to drive 7 segment display directly with the Arduino (with resistors on each segment). 

That PCB you show above also has 14 segments (7 for each number).  

You can use multiplexing to drive the segments with 9 (or less) pins on the Arduino so you're not using up all of your digital I/O pins.

Here's a good example: https://www.instructables.com/id/Arduino-7-segment-countdown-timer/

Note: Instructables has numerous projects on this very topic. Just search for "7 segment display arduino"

At a guess:
I would say that D0-D3 were the data lines for the number.
Digit was like a chip select, selecting which 7-seg is changed with the data lines.
+9v+5v and GND are most likely either a 9or5 volt supply, and a ground.

I suspect the board has a display driver and so the data lines will need to be given BCD.
When programming, change digit befire the data lines, or the wrong number (or both) may change.

And if you were going to place this into a box or case, note that the dots will be decimal points, and so your first picture is upside down, probably.

Also, what does the text in the corner of the PCB say? Try googling it to get a datasheet.

 i couldnt find it but it says 060406 display-pcb REVO5 
do you know what i would wire the D0 -D3 and digit to on the Arduino 

I would suggest that D0 is the LSB, and to connect it over an output port of the Arduino. That way you can output a number to the port and have it display.

But I do not use an Arduion, and so you might benefit from asking someone else for more specific help.