Abstract: A system comprises an integrated package including a microcontroller having a vehicle bus controller, e.g., a CAN controller, for communicating directly with a vehicle bus, the microcontroller being always active; and a microprocessor having a communication module for communicating with the microcontroller, and not having a vehicle bus controller for communicating directly with the vehicle bus. The system may further include a power switch circuit for enabling the microcontroller to control power to and the state of the microprocessor. The microcontroller and the microprocessor may intercommunicate via a dedicated channel. The microcontroller may also have a hard-coded sequencer for enabling the microcontroller to load microcontroller control code into internal RAM of the microcontroller, which it receives from the microprocessor.

Abstract: Recording or playback devices for optical recording carriers have a servo control circuit which controls the tracking and the focus of an optical scanning unit 1 with reference to an error signal. According to the invention, the error signal is non-linearly amplified upstream of the servo controller, in order to process strong external mechanical effects, normally referred to as shocks, in such a way that the tracking and the focus are retained or adjusted. If there is a defect, such as a scratch on the disc etc., a defect detector and a linear amplifier connected in parallel with the non-linear amplifier are additionally used, the linearly amplified or non-linearly amplified error signal being fed to the servo controller as a function of the output signal of the defect detector. The sign of the error signal, which includes direction information, is retained in the case of the non-linearly amplified error signal.