Switch - Not defined in this scope

Using Arduino Programming Questions
1

I changed the sample routine of my keypad shield for getting the current button. Instead of separate if clauses I now use if else, ... However, now it throws a not defined error for all constants declared by #define. If I change this definitions to constants, same happens. What's the trick?

int lcd_key     = 0;
int adc_key_in  = 0;
int lastButton  = 0;
int curButton   = 0;
#define btnRIGHT  0
#define btnUP     1
#define btnDOWN   2
#define btnLEFT   3
#define btnSELECT 4
#define btnNONE   5

int read_LCD_buttons()
{
  adc_key_in = analogRead(0);  // read the value from the sensor
  
  if (adc_key_in < 50)
    curButton = btnRIGHT;
  else if (adc_key_in < 195)
    curButton = btnUP;
  else if (adc_key_in < 380)
    curButton = btnDOWN;
  else if (adc_key_in < 555)
    curButton = btnLEFT;
  else if (adc_key_in < 790)
    curButton = btnSELECT;
  else 
  curButton = btnNone;

  if (curButton == lastButton)
    return btnNone;
  else return curButton;  // when all others fail, return this...
}
2

You define 'btnNONE', then try to use 'btnNone'.

And it's not for all defines like you said, just for that one.

3

lastButton never changes

4

:slight_smile: You helped me out a lot. I was so blind. Such a trivial thing. Already spend one hour and could not find it. Thanks!

Assignment of last button is inserted now, the function was not finished.

5

Now you know. When you get an error like that, look very carefully at the named variables and check the spelling.

6

Spelling, AND capitalization.

7

For C-based languages I include capitalization with spelling. ASCII 65 is not equal to ASCII 97.