When you buy a pack from Adafruit, it comes with the fully tested and
assembled backpack as well as two dual 14-segment display in one of the colors
we provide (say, red, yellow, blue or green). You'll need to solder the
matrix onto the backpack but it's an easy task.
Remove the parts from packaging and place the LED matrices OVER the silkscreen side. DO NOT PUT THE DISPLAY ON UPSIDE DOWN OR IT WONT WORK!! Check the image below to make sure the 'decimal point' dots are on the bottom, matching the silkscreen.
Check your work, making sure each pin is nicely soldered, and there's no cold solder joints or shorted pins
Prepare the header strip:
Cut the strip to length if necessary. It will be easier to solder if you insert it into a breadboard - long pins down
Add the Backpack:
Place the backpack board over the pins so that the short pins poke through the breakout pads
That's it! now you're ready to run the firmware on your Arduino!
