I ordered this 2 Digit 7 Segment Display (https://www.amazon.com/a13071500ux0886-Cathode-Segment-Display-Digital/dp/B00EZBER4K/ref=cm_cr_arp_d_product_top?ie=UTF8) set a few days ago, and received 5 working 2-digit 7-segment displays. They each have 10 pins, which I had to figure out through testing that this is their pin layout (Attached). I'm able to display the same character on both at the same time, as well as only on one digit, but I haven't figured out how to display different characters at the same time. Does anyone know how I could accomplish this?
Multiplexing. First display the left hand digit then change and display the right hand digit . Do this cycle quickly enough and it will appear that both digits are displayed simultaneously.
Use a max7219 chip. One chip can drive up to 8 digits. This chip will perform the necessary multiplexing for you and minimise the other components needed (one resistor and two capacitors). Multiple chips can be chained together so that only 3 Arduino pins are needed to control them all.