Custom
((volatile struct Custom *)0xdff000)->color[0] = 0xa00; /* RED */
((volatile struct Custom *)0xdff000)->color[0] = 0xAA0; /* YELLOW */
((volatile struct Custom *)0xdff000)->color[0] = 0xA70; /* ORANGE */
((volatile struct Custom *)CUSTOMADDR)->color[0] = 0x0a0; /* GREEN */
((volatile struct Custom *)CUSTOMbase)->color[0] = color;
#define custom (*((volatile struct Custom *)CUSTOMbase))
#define CUSTOM_OFS(field) ((long)&((struct Custom*)0)->field)