A control system is provided for use in a power tool. A dead time between pulses generated by a switching circuit is adaptively set in conformity with a value of the input voltage to the resonant switching power converter and an indication of a magnitude of the current passing through inductive element of the resonant tank of the converter. Access is switched from the first area of the memory card to a second area of the memory card if specified data follows the received command allowing for the memory access switch. As the processor commences execution in speculative mode, it stores copies of instructions as they are issued into a recovery queue. Therefore, even in the case of the occurrence of the data missing area in the memory in which the error correction data indicating the presenceabsence of errors in the main data is written over existing data and stored, the errors in the main data are corrected properly in accordance with data output from the memory. A stroke sensor measuring a stroke amount, and a shift load sensor making a stroke motion in extension and contraction directions in accordance with shift-up and shift-down operating loads from the gear shift pedal are integrally provided to the shift rod.