Computer questions: how car computers work

As the years go by, the makeup of cars become more complicated. Today cars may have as much as 50 microprocessors in them. The increase in the number of microprocessors is in part because of advanced diagnostics, new safety features, new comfort and convenience and simplification, according to Irvine auto glass. These factors and many more are what make the design of cars better.

It was possible for car engines to be built without microprocessors before emission laws were passed. With the enactment of the stricter emission laws, more sophisticated control themes were required to make the air/fuel mixture regular so that pollution could be removed from the exhaust using the catalytic converter. Controlling the engine is the most import processor job on a car. The most powerful computer on most cars is the engine control unit. The engine control unit uses closed loop control to manage the engines emissions and fuel economy. The engine control unit is very important and it uses calculations and date to make sure that the car gets the lowest emissions and best mileage.

The engine control unit is packaged with many other components that support the processor. The analog-to-digital converters are devices that look at the outputs of some of the cars sensors. Because the processor only understands digital numbers, the analog-to-digital converter changes the voltage into 10-bit digital numbers. High-level digital outputs are required for the engine control unit to fire spark plugs, open and close fuel injectors and turning the cooling fan on and off. The digital-to-analog converts digital numbers into an analog voltage. This is needed because the processor is a digital device and sometimes the engine control unit has to have an analog voltage output to drive some of the components. Signal conditioners are circuits that adjust the level of the signals that come in or out because at times inputs or outputs must be adjusted before they are read. Communication chips are chips that scan the many different communication standards that cars use. Many standards are used but the one most frequently used is CAN (controller-area-networking), it allows for connections speeds of up to 500 kbps making it much faster than older standards. Faster speeds are becoming more and more necessary.

The new communication standards have made the designing and building of cars easier. One of the advantages of a communication bus is that each module can let the central module know about faults, which stores them and communicates them to an off-board diagnostic tool. This is useful so that technicians can diagnose problems with the car. It is especially good with intermittent problems because they are notorious for disappearing as soon as you bring the car in for work.

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