position sensor 44 which can be provided as a resolver of the electric machine 14 the engine position information is used to generate a signal that represents the position of cylinder 1 i e the first cylinder in the firing order on a 720 degree scale i e two crankshaft revolutions of 360 degrees each for one complete engine cycle in which all cylinders go thru a complete cycle of intake compression ignition and exhaust top dead center tdc of cylinder 1 during the compression stroke represents zero degrees the engine position sensor 45 can not be used to determine the rpm and position below a low value of rpm e g approximately 100 rpm or in the reverse direction rotation of the crankshaft in the reverse direction can be detected by the control module 34 but the rotation appears the same as the rotation in the forward direction the em position sensor 44 can determine the em position and rpm em down to zero rpm because the electric machine 14 and the engine 12 are coupled by a belt of fixed ratio rpm em and the em position can be used to determine rpm eng and engine position below the point where engine position sensor 45 no longer detects rotation as.