.logicQuirks) this.v[0xF]=0; break;
			case 0x4:
				var t = this.v[x]+this.v[y];
				this.writeCarry(x, t, (t > 0xFF));
				break;
			case 0x5:
				var t = this.v[x]-this.v[y];
				this.writeCarry(x, t, (this.v[x] >= this.v[y]));
				break;
			case 0x7:
				var t = this.v[y]-this.v[x];
				this.writeCarry(x, t, (this.v[y] >= this.v[x]));
				break;
			case 0x6:
				if (this.shiftQuirks) { y = x; }
				var t = this.v[y] >> 1;
				this.writeCarry(x, t, (this.v[y] & 0x1));
				break;
			case 0xE:
				if (this