C Definition in sketch to configure library

[Robinek70]

Hello,

I'm trying to write own library.
I would like to library was configurable from sketch by #define MY_USE_ADC_FILTER similar like configuration MySensors.
But my library don't see definition from sketch in my .h and .cpp files.

I don't know how it is done in MySensors library.
Could someone just explain how to achieve similar behaviour?

Thanks
Robert

[mfalkvidd]

@Robinek70 are the defines in the sketch before including the library? That should be sufficient. If they already are, could you share your code?

[Robinek70]

it is something like below.
Definitions
#define MY_USE_ADC_FILTER
#define MY_ADC_PIN
are not visible in .h and .cpp.
I don't know what I'm doing wrong :(

//test.ino
#define MY_RADIO_NRF24

#define MY_USE_ADC_FILTER
#define MY_ADC_PIN

#include <RPlibs.h>
#include <MySensors.h> 
...

//RPlibs.h

#ifndef MY_ADC_PIN
  #defie MY_ADC_PIN  A0
#endif

#define DT_FILTER  10
int getAdc();

//RPlibs.cpp
#include <RPlibs.h>
static int prevValue ;
int getAdc() {
  int value = analogRead(MY_ADC_PIN);
  #ifdef MY_USE_ADC_FILTER
      prevValue = (prevValue *DT_FILTER  + value) / (DT_FILTER  + 1);
  #else
      prevValue = value;
  #endif
  return prevValue 
}

[mfalkvidd]

This works for me
sketch.ino

#define MY_RADIO_NRF24

#define MY_USE_ADC_FILTER
#define MY_ADC_PIN

#include "RPlibs.h"

RPlibs.h:

#ifdef MY_USE_ADC_FILTER
#error "Define ADC set!"
#else
#error "Define ADC not set!"
#endif

With the define, the build process outputs

In file included from C:\Users\Micke\AppData\Local\Temp\arduino_modified_sketch_472392\sketch_sep20a.ino:6:0:

RPlibs.h:2: error: #error "Define ADC set!"

 #error "Define ADC set!"

and without the define it outputs

In file included from C:\Users\Micke\AppData\Local\Temp\arduino_modified_sketch_303778\sketch_sep20a.ino:6:0:

RPlibs.h:4: error: #error "Define ADC not set!"

 #error "Define ADC not set!"

[Robinek70]

it's very strange for me.
I checked under two environments:
Arduino 1.6.7 and Visual Studio 2012 with plugin Visual Micro.
And my result of tests:
directly under Arduino, .h file see definition from sketch, but .cpp file don't :(
under VS definition isn't visible in .h and .cpp files.

[Robinek70]

full test files

File in path Arduino/Test/

//test.ino
#define MY_RADIO_NRF24

#define MY_USE_ADC_FILTER 

#include <RPlib.h>

void setup() {
}

void loop() {
  Serial.println(getAdc());
}

Files in path Arduino/libraries/RPlib/

//RPlib.h
#ifndef MY_ADC_PIN
  #define MY_ADC_PIN  A0
#endif

#define DT_FILTER  10

int getAdc();

//RPlib.cpp
#include <RPlib.h>
#include <Arduino.h>
static int prevValue;

int getAdc() {
  int value = analogRead(MY_ADC_PIN);
  #ifdef MY_USE_ADC_FILTER
		#error  FILTER
      prevValue = (prevValue *DT_FILTER  + value) / (DT_FILTER  + 1);
  #else
	#error  NO FILTER
      prevValue = value;
  #endif
  return prevValue;
}

I always got
#error NO FILTER