I bought MAX7219EWG chips and I already have a lot of common-cathode 7 segment displays. I used the LedControl library for the Arduino for testing purposes.
Firstly I just wanted to see if only one single 7 segment display will work.
I hooked up all the segments to the chip, I connected DIG0 to the common cathode of the display, DataIn to pin 12 of the arduino, CLK to pin 11, and finally LOAD to pin 10. I hooked up the ground and +5V, uploaded the program and I saw nothing.
I checked all the wiring and I don't think that's the problem. Then I thought maybe the display itself is not working and I got a common-anode display just so I can test it with that. I hooked it up and it lit up, constantly showing the number 8, basically all the leds are on. It's kinda weird. I looked at the datasheet of the MAX7219 and it says it's for driving common-cathode displays, but in my case it doesn't work.
I am sure that the displays I have work since I have used them in other projects and also I am sure that they are common-cathode because I tested them with a multimeter.
Can someone please suggest a solution to this.
Any help will be appreciated.
Thanks in advance.