I bought some 7-segment displays that I want to display a speed on.
The issue I just realized is that they are common-anode, which will not work with the max7219.
Bummed cause the 7-segments are just right looking 2" and blue :-/
Do I have any options other that find new ones?
I would think there is some chip that would drive it
The MAX7219 looks like rather a good chip! It handles both the anode and cathode drive requirements of the LEDs. I was going to suggest making an LED driver circuit out of 74HC595 chips, as shown in one of the tutorial examples, but then you'd still need to make your own anode drivers (PNP transistors) and do all your own multiplexing. Might be easier to find replacement LED displays.
Can someone please explain the bit about making your own anode drivers?
Does this mean there is a method of driving a common anode or cathode display from a device that runs the opposite by using PNP or NPN transistors?
I have some 595's that are common cathode that I would like to drive a common anode matrix if possible.
OK, for the anode drivers, one way is to use PNP transistors (or P-channel MOSFETs) and make a so-called "high side driver". Try doing a web search on that term and see what you get! If you have no luck, post another message here and I'll see if I can come up with a circuit diagram (schematic).
Thanks. I have found that the 595 shift registers will output either +5 or ground (through the use of transistors I believe) so I am using one of those to drive the common anode of my LED array at the moment.