Calling functions from other documents

[Kilroy0846]

In MPLAB, how do I call functions from other files in a project?

Here is my code:

static int counter;

counter = Get_Encoder_3_Count();

And the Get_Encoder_3_Count() function is located in the file encoder.c

Here is the function code:

long Get_Encoder_3_Count(void)
{
	long count;

	INTCONbits.RBIE = 0;

	count = Encoder_3_Count;
	
	INTCONbits.RBIE = 1;

	return(count);
}

The error that I get is:

Error - could not find definition of symbol 'Get_Encoder_3_Count' in file 'V:\frc-code-2007-8722\FrcCode_2007_8722\user_routines.o'.

[dcbrown]

declare the function reference as external to your source file.

extern long Get_Encoder_3_Count(void);

[tdlrali]

are you #include'ing?

[Kilroy0846]

I have the both the files encoder.c and encoder.h included. I added the external identifier, but I still get the same error.

Here is my new code:

static int counter;
extern long Get_Encoder_3_Count(void);

counter = Get_Encoder_3_Count();

[JohnC]

If you're using more than one function from a file, you could just include that file's header file. Use quotes if it's not a library that comes with the compiler.

#include "myfile.h"

[Kilroy0846]

I Have the code:

#include "encoder.h"
#include "encoder.c"

located at the top of the document

[dcbrown]

It sounds like you haven't set up the encoder stuff correctly. Not all the encoder code is enabled by default. If that's the case then that routine isn't being compiled - its being excluded because ENABLE_ENCODER_3 isn't defined.

There is an encoder_readme.txt file in the documentation directory and there is info in the encoder.h file. Is the ENABLE_ENCODER_3 line in .h un-commented?

[Chaos in a Can]

You don't need to include "encoder.c", and in fact, you probably shouldn't.

I don't think that's the problem, but if you include a .c file, you're probably going to get an error about something like multiple declarations of something.

The headers tells the file that a function exists somewhere in one of the .c files. The actual code for that function doesn't need to be in the same .c file the function is used in.

[Alan Anderson]

Take a few steps back. Undo everything you've tried to do in order to make it work. Read the documentation (I think it's called encoder_readme.txt) that comes with the encoder software. Follow the steps (nine of them, if I recall correctly) to add the code to your project and configure it.

If it still doesn't work, let us know.

[ShotgunNinja]

Originally Posted by Kilroy0846

In MPLAB, how do I call functions from other files in a project?

Here is my code:

static int counter;

counter = Get_Encoder_3_Count();

And the Get_Encoder_3_Count() function is located in the file encoder.c

Here is the function code:

long Get_Encoder_3_Count(void)
{
	long count;

	INTCONbits.RBIE = 0;

	count = Encoder_3_Count;
	
	INTCONbits.RBIE = 1;

	return(count);
}

The error that I get is:

Error - could not find definition of symbol 'Get_Encoder_3_Count' in file 'V:\frc-code-2007-8722\FrcCode_2007_8722\user_routines.o'.

The problem could be that you tried to return a 'long' (4 bytes) variable into an 'int' (2 bytes) holder. Let me know if that helps any.