yasu made AR codes to play Mario Kart with the paddle from Arkanoid ! http://home.usay.jp/pc/etc/nds/index_en.html To quote him: I tested it on R4DS. Press START+SELECT first, then controll paddle instead of D-Pad! If you press left or right of D-Pad, center point of paddle will be initialized. here are sample codes: REG_EXMEMCNT |= 0x23; // set wait cycles uint8 value_low = *(vuint8*)0x0A000000; uint8 value_high = *(vuint8*)0x0A000001; the value is 12bit. I think the high cannot be read before reading the low. Anyone able to try this?