Time-dependent signal providing method for controlling microprocessor in motor car environment, involves periodically activating and deactivating generators, comparing frequencies of clock signals and adjusting divisor based on comparison

摘要

The method involves dividing clock signals of a clock generator i.e. oscillating circuit (110) with inaccurate clock frequency by a divisor. A time-dependent signal is provided based on the divided clock signal divided by the divisor. Another oscillating circuit (115) is periodically activated and deactivated for providing another clock signal with a precise clock frequency. Frequencies of the clock signals are compared, and the divisor is adjusted based on the comparison. An external signal is generated. Independent claims are also included for the following: (1) a computer program product having a set of instructions for providing a time-dependent signal (2) a timer comprising a clock generator for providing a timing signal.