I have a whole tray of these 7-segment displays that I pulled out of boards at work that someone threw in the garbage. I've had them for well over 10 years. Every now and then, one comes in handy. I was bored while I waited for parts for my IN-18 Nixie Clock to arrive from China. I wanted to throw together a silly little ATtiny thing that could use a 7-segment display to display a random number from 0-9. Nothing fancy, just a silly little one-day project.



Since these displays are very much obsolete, I had to create my own EAGLE part.



I figured out the pinouts and mapped the pins to the pads.



I then threw together a silly little thing that would use an ATtiny84 to push out a BCD value to a 7447 BCD-to-7-Segment decoder. I had plans to also add a transistor that would power a high powered LED, but that part of the circuit for some reason doesn't work. Oh well, I guess no blinky-blinky.



Anyway, I created the PCB and sent it off to have it fabbed.



Two weeks later, I had my boards in hand. Just in time for the weekend too!



I soldered all the SMD stuff along with the DC regulator. I connected a 9V battery and dialed in the regulator to 5V.



I then soldered all the other components in and uploaded my sketch. And there it is. You push the button, and it gives you a random number.



I then made a little case for it. Again, nothing fancy. I wanted to bang this thing out in a single afternoon, so it is what it is.



All done.



This will come in very handy when the kids argue over who gets the last donut or whatever. Hey kids….pick a number!