Runtime / Simulation Specific Code

the preprocessor, which handles the #... thingies do NOT look at char, int etc.

thus if you have
#ifdef RALPH

RALPH must be a #define

the ussual way to do this is in xxx.h to have something like
//#define BUILD1 //uncomment this line for build1

Erik

the preprocessor, which handles the #... thingies do NOT look at char, int etc.

thus if you have
#ifdef RALPH

RALPH must be a #define

the ussual way to do this is in xxx.h to have something like
//#define BUILD1 //uncomment this line for build1

Erik

So you're saying I would just need to change all my:

if(DiagMode==1)

statements to

#if(BUILD1)

Is that correct? I just want to make sure before I change my whole program.

Thanks, Erik!

Note that #if BUILD1 tests if the preprocessor symbol BUILD1 is nonzero.
#if defined(BUILD1) (or the older #ifdef BUILD1) just tests if it is defined.

#define BUILD1 // just defines this symbol
#define BUILD1 1 // also gives it a value

if you give the define a value, you can also do

#define BUILD_TYPE 2

#if BUILD_TYPE==0
    ...
#elif BUILD_TYPE==1
    ...
#elif BUILD_TYPE==2
    ...
#else
    #error "Unsupported build type."
#endif

Well, found the issue with the errors with

#define DiagMode 0

in my VARS.H file. Turns out, I just need to comment out:

unsigned char idata DiagMode = 0;
extern unsigned char idata DiagMode;

Now I don't have to change anything (which is convenient). Thanks!

Well remember that #define does symbol replacement.

So your

unsigned char idata DiagMode = 0;

will look like

unsigned char idata 0 = 0;

and the compiler is not impressed by that.

So you're saying I would just need to change all my:

if(DiagMode==1)
statements to

#if(BUILD1)
Is that correct? I just want to make sure before I change my whole program.

of course not, Names in an example are just that

Erik

Ok, now I'm confused. What is it you guys are proposing me to do at this point?

Originally, I had:

VARS.H

#ifndef _D4_VARS_H
#define _D4_VARS_H

extern unsigned char idata DiagMode;

vars.c

#include "VARS.H"
unsigned char idata DiagMode = 0;

main.c

#include "VARS.H"
void main (void)
{
        DiagMode = 0;

        /* Loop for standard/hardware diagnostics mode */
        if ((DiagMode == 0) || (DiagMode == 2))
        {
                while (1)
                {
                        // Insert code here
                }; /* Loop forever */
        }
        /* Loop for simulation/software diagnostic mode */
        else if (DiagMode == 1)
        {
                while(1)
                {
                        decimator2_ISR();
                        // Insert code here
                };      /* Loop forever */
        }

}

I have now changed it to:

VARS.H

#ifndef _D4_VARS_H
#define _D4_VARS_H

//extern unsigned char idata DiagMode;
#define DiagMode 0

vars.c

#include "VARS.H"
//unsigned char idata DiagMode = 0;

main.c

#include "VARS.H"
void main (void)
{
        DiagMode = 0;

        /* Loop for standard/hardware diagnostics mode */
        if ((DiagMode == 0) || (DiagMode == 2))
        {
                while (1)
                {
                        // Insert code here
                }; /* Loop forever */
        }
        /* Loop for simulation/software diagnostic mode */
        else if (DiagMode == 1)
        {
                while(1)
                {
                        decimator2_ISR();
                        // Insert code here
                };      /* Loop forever */
        }

}

This appears to work as I can change the Diagmode = 0 to 1 and it gives me a different code size, which I assume means it's working (maybe I'm wrong). Am I doing this right or are you suggesting I need to do it a bit differently?

I understand that you guys generally want to give guidance without giving sample code but at this point, I think you're losing me with what it is you're suggesting. Can you give me a quick code example for what you think I should be doing because, if I'm doing something incorrectly right now, I really don't understand what it is you are suggesting.

Look at my example.

I have a question for you. So, if you look at my last post, you can see what I did and it seemed to work without updating any of my if statements to #if statements. Is this because Keil fixed the issue for me with the compiler (which probably means I am still doing it incorrectly, regardless of how Keil fixes it for me) or is what I did actually correct?

I found an area that had an if/else diagmode statement and changed them to #if and #else and noticed no change in code size (ie the code I had was executing correctly with my fixes) so it appears to be doing what I wanted it to do correctly.

I just want to know if my procedure is incorrect and, for best practices or when using other compilers (or even changing optimization levels, possibly), I need to implement it differently or if my coding is correct.

Let me know if my wording is confusing and I can try and explain it again. Thanks!

you are mixing precompiler and compiler directive

THIS IS AN EXAMPLE VARIABLE NAMES ARE FICTIONAL

common.h

//#define OMIT1 //uncomment if certain code is to be omitted
//#define OMIT2 //uncomment if certain other code is to be omitted

whatever.c

#include common.h

code
#ifndef OMIT1
code that is to be excluded if omit 1
#endif
code
#ifndef OMIT2
code that is to be excluded if omit 2
#endif
code
#ifndef OMIT1
more code that is to be excluded if omit 1
#endif
code

Ok, I understand.

Out of curiosity, is it really easier to create your own examples from scratch rather than to simply demonstrate by correcting code that is incorrect (such as my examples)? Could save a few posts.

Oh, and for the record, I don't want to come off as ungrateful because I do appreciate the help I'm getting.

And so you know, I used "BUILD1" for reference purpose, not because I thought BUILD1 was the required variable (I understand you weren't being literal with that name). So that part wasn't lost on me, in case I gave you the impression I didn't know how variables worked . . . :p

The compiler is smart. If it see C code that is unreachable, it can remove it.

So:

int charlie=1
if (charlie == 1) {
    ...
} else {
    ...
}

the compiler can throw away the code inside the else statement.

If the code instead looks like:

void my_function(int charlie) {
    if (charlie == 1) {
        ...
    } else {
        ...
    }
}

Then the compiler can't throw away any code.

But when using #ifdef x or #if defined(x) or #if x == y then the preprocessor will filter away non-matching code and the compiler don't need to worry about what can be resolved at compile time and what needs to be resolved at runtime.

Out of curiosity, is it really easier to create your own examples from scratch rather than to simply demonstrate by correcting code that is incorrect (such as my examples)?
I consider it more important that you get to understand how this works than giving you code.
Giving you code will not help you next time

Erik

I don't do it because i worry about "giving code". I do it because I want to show a skeleton showing the concept without any extra noise around.

Remember that threads on this forum are read by people who find the threads using search engines at a much later time. They don't care about your specific source code. But they may care about the concept that is covered in the thread.

So it's likely that Keil is overcompensating for errors in my code. I should still use the #if statements rather than if statements, even if it seems to be working correctly, just to play it safe. Thanks for the help.