Connect 2 independent 7-Segment Displays?

Using Arduino Displays
1

Hello everyone,

First of all I need to apologize to you all for my english, and I'm going to try to explain this to you as well as I can. I've been looking for a solution for this problem all afternoon without any positive result, so I decided to post it on the forum.

I'm doing a project where I need to connect 2 independent 7-Segment Displays on my Arduino Board. I wanted there to be random numbers from 0 to 9 on both of the displays. (They should display different numbers almost every time).

However, I do not want to use 8 pins (4 bit per display) on the Arduino Board, but I am willing to connect some components (such as Multiplexer and decoder).

Is there any way I can do this? (I don't need any code by the way, I just want to know how to use less than 8 pins)

Here is a scheme of what I came up with earlier, for just one display:

1x arduino pwm pin ---> Homemade DAC (made with resistor and capacitor) --->
---> ADC ---> 7-Segment display decoder ---> 7-segment display

But I'm sure there's a quicker and better way of solving this problem.

Thanks and have a nice day :slight_smile:

Piero

2

If you chain together two 74HC595 chips, you can use 3 Arduino pins to drive 16 outputs.
It should be easy to find information and examples on how to wire it up and how to use it.

3

4

Much easier.

Get a MAX7219.

It's just as cheap to get one of these modules from eBay and use the PCB with the MAX chip for your connections.

Mind you, just as cheap to buy the whole display.

5

Alright thanks everyone for your help!
Have a nice day :slight_smile:
Piero