Need help: charlieplexed 5-digit button counter

Hi guys,

I’m constructing a 5-digit button counter that can count up to 99,999. I’ll be using 5 charlieplexed 7-segment displays, without drivers or transistors. Attached is a sample of the connection of the 7-segment displays. Is it possible to connect five 7-segment displays without using transistors? I also need help in the code to control all 5 digits. I’ve seen a lot of sample codes for charlieplexed displays, but it doesn’t work with my circuit. How do I control each of the displays? I’ve only managed to code one 7-segment display. Please help. Thanks. :slight_smile:

charlieplexed display.JPG

I can't see how you think this is a charlieplexed circuit. It just looks like a normal multiplexed circuit to me. Even so it won't work because you have only one resistor in the common anode (or cathode), that means the brightness of a segment is dependent on how many segments are on at any one time. That means you are restricted to only having one segment on at any one time. For 5 displays this gives you a multiplex ratio of 35 to 1, so the segments will probably be too dim to see.

without drivers or transistors

Is your problem.