C-Macros produces unexpected behavior

Question

I'm trying to make my header file easily changeable with macros. I'm debugging my code and it seems these MACROS are not doing what they are supposed to. Can someone tell me how I achieve the following effect? LED_ID_AMS etc.

#define LED_NUMBER                  (2)
#define LED_ID_X                    (0)
#define LED_ID_Y                    (1)
#define LED_PIN_X                   (0)
#define LED_PIN_Y                   (3)
#define LED_PORT_X                  (PORTE)
#define LED_PORT_Y                  (PORTG)
#define LED_DD_X                    (DDRE)
#define LED_DD_Y                    (DDRG)
#define LED_PORT(LED_ID_X)          (LED_PORT_X)
#define LED_PORT(LED_ID_Y)          (LED_PORT_Y)
#define LED_PIN(LED_ID_X)           (LED_PIN_X)
#define LED_PIN(LED_ID_Y)           (LED_PIN_Y)
#define LED_DD(LED_ID_X)            (LED_DD_X)
#define LED_DD(LED_ID_Y)            (LED_DD_Y)

What am I trying to achieve?

I'm trying to make it so I can loop through the port init like so:

for(i=0;i<LED_NUMBER;i++){
    /* set data direction to output*/
    LED_DD(i)|=((0x01)<<LED_PIN(i));
    /* turn on led */
    LED_PORT(i)|=((0x01)<<LED_PIN(i));
}

Answer 1

You will regret using too many macros later. Actually, you're regretting it already, as they don't work and, being macros, they are very difficult to debug.

Just a few points:

• your LED_PIN(i) expressions are always expanding to 0
• your LED_PORT(i) expressions are always expanding to PORTE whatever that may be

For instance LED_PIN(LED_ID_X) expands to LED_PIN_X. Note, macro parameter LED_ID_X is not used at all. Instead, LED_PIN_X simply expands to 0.