A power tool and method of detecting impacts of a power tool that includes a motor driving a hammer to impact an anvil. A motor control unit is configured to determine a motor characteristic indicative of a speed of the motor. When the motor characteristic indicates that the speed of the motor is below a speed threshold, the motor control unit employs an acceleration-based technique to detect a first impact based on a change in motor acceleration and generate a first impact indication in response to detecting the first impact. When the motor characteristic indicates that the speed is above the speed threshold, the motor control unit employs a time-based technique to detect a second impact based on an elapsed time and generates a second impact indication in response to detecting the second impact.