test.c

#include "gba.h"

typedef struct __attribute__((packed)) {
  hword data[ 16 ];			// Sprite graphic data
} character16;

character16 characters[] =
{
    {
        {
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111,
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111
        }
    }, // Ball
    {
        {
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111,
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111
        }
    },
    {
        {
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111,
            0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111, 0x1111
        }
    } // Racket
};

int main()
{
    int i, j;
    volatile hword *ptr;
    volatile character16* chptr;
    volatile sprite* sp;

    // Initialize background (green)
    gba_register(LCD_CTRL) = LCD_OBJMAP1D | LCD_MODE0 | LCD_OBJEN;
    ptr = (hword*) BG_PALETTE;
    ptr[0] = BGR(0, 31, 0); // backdrop color

    // Initialize ball and racket
    // Set pallet
    ptr = (hword*) OBJ_PALETTE;
    ptr[0] = BGR(0, 0, 0);
    ptr[1] = BGR(31, 31, 31);
    // Set characters
    chptr = (character16*) OBJ_CHAR_TILE;
    for (i = 0; i < 3; i++)
    {
        for (j = 0; j < 16; j++)
            chptr[i].data[j] = characters[i].data[j];
    }
    // Set ball OAM
    sp = (sprite*) OAM;
    sp[0].attr0 = OBJ_SHAPE_SQ + 50;
    sp[0].attr1 = 0x0000 + 50;
    sp[0].attr2 = 0x0000;
    sp[0].padd = 0x0000;
    // Set racket OAM
    sp[1].attr0 = OBJ_SHAPE_HR + 50;
    sp[1].attr1 = 0x0000 + 50;
    sp[1].attr2 = 0x0000 + 1;
    sp[1].padd = 0x0000;

    while(1);
}