Zero Gunner 2 Rom board type 171-7978B Rom 0 Ic 22 Epr 23689 Rom 1 IC 1 (IC1/IC2) MPR 23684 Rom 2 IC 2 (Ic3/Ic4) MPR 23685 Rom 3 IC 3 (IC5/Ic6) MPR 23686 Rom 4 IC 4 (Ic7/Ic8) MPR 23687 Rom 5 IC 5 (Ic9/Ic10) MPR 23688 Protection Chip 317-5073-Com 315-6213 315.6319A