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Need help trying to get the Arduino working with the RGB Matrix (with backpack) and an EEPROM chip. Answered

Hi everyone, first question on instructables! I have an Arduino Deumilanove, a Sparkfun RGB Matrix with backpack, and an EEPROM chip (24LC256). I have the Arduino all hooked up to the matrix and have been able to mess around with some basic images and colors, but I have a lot of questions. So far, to display letters I have been setting up sections of code that light up each LED separately. I know there has to be a more efficient way to do this and was wondering how? Also, I have an EEPROM chip that is setup with the Arduino and Matrix but can't figure out how to use it. I have looked at the code for it on the Arduino website and I can't really figure out how it all works. So basically, here's what I want to be able to do: - Store the alphabet in the EEPROM - Be able to recall letters from the EEPROM - Display marquee messages Thanks in advance!



10 years ago

Show your working.... Presumably you are using C to program this ? Or are you in assembler ? Storing character maps is usually done with constant arrays in your code. I'd put the "alphabet" in ROM, and my messages in EEPROM. Displaying smoothly running marquee messages should wait until you've mastered the first two bits. Steve


Answer 10 years ago

Well, here is what I can tell you, first, in your code you need to include the EEPROM library in order to communicate with it. Information about the basics can be found at http://arduino.cc/en/Reference/EEPROM. In the Arduino and Sparkfun site's forums, there is a basic code example of storing hex information in the EEPROM. Again here is a link, http://forum.sparkfun.com/viewtopic.php?t=10805.

Beyond that, I am trying to figure out how to scroll text also, I have no idea how to go about doing it and as now I can flash individual characters on the screen using the Hex values, which also allows me to frame by frame animations, but there has to be a better way. Seems like a lot of people are a bit stingy with their code on those forums and I wish they weren't since I have the RGB backpack also, and most code is written for the max7219.