Abstract: A control unit that includes a processor having at least a first chip select output and a second chip select output. A signal provided by the first chip select output is activated during a normal operating mode of the control unit, and a signal provided by the second chip select output is activated during an application mode of the control unit. The control unit also includes a RAM memory having a chip select input for selecting the RAM memory and having a memory area for use as an application memory. A combination element electrically couples the signal provided by the first chip select output and the signal provided by the second chip select output to the chip select input of the RAM memory such that the signal provided by the first chip select output and the signal provided by the second chip select output do not have a perturbing effect on each other.

Abstract: The method is used to store and retrieve data in a control system, in particular in a motor vehicle, which contains a computer, a RAM memory and a flash memory. When the control system is switched off, operational data of different types, which can change while the control system is operating and which are required again after the control system is switched on again and which are stored in the RAM memory, are then stored in the flash memory. The flash memory is managed by means of a circular buffer method and can hold multiple copies of the operational data of the same type. When the control system is switched on, the most recent operational data of a respective type of data are determined and output to the RAM memory.

Abstract: In a control unit, particularly for use in a motor vehicle, time measurement and time control should be independent of computer-specific cycle times. The control unit includes a quartz-controlled timer with a specified clock frequency and a global timer clocked by the quartz-controlled timer. The global timer furnishes a global timing pulse as a reference time for all the program parts of the computer. A plurality of dynamically managed program-controlled timers, which receive their clock signal from the global timer, are requested by the computer program each for one time measurement associated with a specific task. After the specific task is completed, the timer is available for further tasks.