The camshaft rotates in phase with the crankshaft, but at half its speed.

凸轮轴和曲轴转, 但速度仅是曲轴的半。

In case that the camshaft signal measured by the first falling edge after dentation is low, then the following TDC would be of the first cylinder.

若缺齿后第个下测到凸轮信号为低，则接下来的TDC是缸TDC。