I started this project by going to thrift stores tirelessly looking for jackets I liked so I didn't have to sew my own, that may come later. I found one I liked and sparkled it up a bit, however I was not satisfied or caught in a grip of inspiration so I decided to take it further!

I ride my bike to and from work everyday, and while I have a few lights already, you can never be too careful, so this is really a matter of life and death.

Thus the idea was born, which is a hard step for me sometimes. ^.^

Next I shlumped through my cabinets of random e-junk and remembered I had nabbed this sweet LED clock with huge 7 segment displays! Check the photos of it.

When I got it I was unable to power it however once I tore it apart I found it was meant to be driven with an AC power supply, which I dont think I even have....

Once I had the badboy open I ripped off all of the parts, essentially everything I would need to drive the displays was already on the board, including a nice set of 7 SN74HC595 Shift Registers :D!

There was also a handful of current limit resistors, high current transistors and a sweet looking LM2575 power IC which I have not looked into. The huge inductor (I think?) that was with it hints at some crazy current source setup, I want to learn more about that.

So far all of the parts, displays and all are working great, I think I was simply ignorant of how to power it when I bought it.

tldr: I ripped the clock apart...

Next I breadboarded up the shift registers to my Trinket and then to the matrix display. I used a handful of assorted transistors that were inside the clock for circuit protection, but I'll only post this circuit on request for two reasons: It seems this part of your circuit is going to be specific to your displays and I am going to be changing the circuit tomorrow to try out a nice ULN2003 instead of all these clunky TO-92's.

I also added in my LDR sensor with a 10k for the other end of the voltage divider, gives me a nice range.

Next I started shifting out random numbers using code I got from the internet which I didnt really read, however it confirmed that my circuit worked, watch my first video to see how it looked.

After mapping out which bits would essentially 'activate' each anode and cathode line, I started sending out patterns of lines. To really test my theory I wrote up a script which would test out the POV action I would need to really get a sweet display.