FIGURE. Main components of the computer and the Microprocessor.
The microprocessor is the brain of the computer. The microprocessor is constructed of thousands of transistors that are placed on a small chip. The microprocessor brings information into and out of the computer’s memory. Hie input information is processed in the microprocessor and checked against the program in memory. The microprocessor also checks memory for any other information regarding programmed parameters. The information obtained by the microprocessor can be altered according to the program instructions. The program may have the microprocessor amicroprocessorly logic decisions to the information. Once all calculations are made, the microprocessor will deliver commands to make the required corrections or adjustments to the operation of the controlled system.
The program guides the microprocessor in decision making. For example, the program may inform the microprocessor when sensor information should be retrieved and then tell the microprocessor how to interpret this information. Finally, the program guides the microprocessor regarding the activation of output control devices such as relays and solenoids. Hie various memories contain the programs and other vehicle data that the microprocessor refers to as it performs calculations. As the microprocessor performs calculations and makes decisions, it works with the memories by either reading or writing information to them.
The microprocessor has several main components. The registers used include the accumulator, the data counter, the program counter, and the instruction register. The control unit implements the instructions located in the instruction register. The arithmetic logic unit (ALU) performs the arithmetic and logic functions.