How can I name my file?!

Projects Programming
1

Hello Arduino Forum!

Wondering if anyone can point me in the right direction as I have no idea where to start. Basically I want to do 3 things:

  1. read the values from 3 potentiometers
  2. ask the user to title the data
    3.write the data to a file on an sd card with the file name being what the user submitted.

I have the code to read and hold values for the pots. How can I have an lcd blink the cursor and scroll through the alphabet so the user can name the file?

Thanks for any help!

2

It's not clear what your are stuck with? If it's the cycling through characters, the below code cycles through the characters 0..9, A..Z and a..z on a keypress.

/*
  returns next character when a button is pressed, else null character
  supports 0..9. A..Z and a..z
*/
char keypress()
{
  // variable to hold character
  static char character = '0';

  // if button pressed
  if (digitalRead(yourbutton) == LOW)
  {
    // next character
    character++;
    // if 0..9, A..Z, a..z
    if ((character >= '0' && character <= '9') ||
        (character >= 'A' && character <= 'Z') ||
        (character >= 'a' || character <= 'z'))
    {
      return character;
    }

    // after 'Z' comes 'a'
    if (character > 'Z')
    {
      character = 'a';
      return character;
    }
    // after 'z' comes '0'
    if (character > 'z')
    {
      character = '0';
      return character;
    }
  }
  else
  {
    // no button pressed
    return '\0';
    // OR
    //return character;
  }
}

No debouncing implemented; not tested. Note that it returns the NULL character if no key was pressed, else the next character. So you need to remember the previous value; or you can change the code to return the last character (as commented at the end).

Note: button wired between pin and ground.

3

There is a simple example of user input in Planning and Implementing a Program

...R