The computer receives voltage signals through an input device. The input device may be a simple button, a switch on the dashboard, or a sensor on the car engine. Signals from switches, engine control modules, and dashboards enter the computer in binary code. Various mechanical, electronic, and electromagnetic sensors used in cars are used to measure parameters such as vehicle speed, engine speed, air pressure, oxygen content in exhaust gas, air flow, and engine coolant temperature. Each sensor converts the information parameter into a voltage signal for transmission. The signal from the sensor is an analog signal, which needs to be processed by input processing, amplifying weak voltage signals, and converting them into binary language used by computers for processing. This processing step can be done internally in the computer, and some sensors themselves have signal processing capabilities.
The electronic logic circuit inside the computer performs operations on the input signals according to its program instructions. These logic circuits convert input voltage signals or data into output voltage signals or instructions. Vehicle-mount computers detect input information to ensure that the circuit for transmitting the information is working properly. The computer knows what voltage each input circuit produces when the input circuit is open. The computer monitors each input signal to ensure that it is between two voltages, otherwise, it will suspect that the circuit is malfunctioning. Sometimes, the computer makes some decisions that are very simple. For example, when the engine coolant temperature is high enough, the coolant temperature/fan indicator light comes on. What the computer needs to do is to observe the temperature and compare it with the set values in the program.
Other decisions are much more complex. When the engine temperature is low or the oxygen sensor cannot provide useful voltage signals due to insufficient temperature, the computer operates in open-loop mode. As long as all conditions are met and the oxygen sensor is working, the computer controls the fuel supply in closed-loop mode. In short, the process of making a decision requires the vehicle mount touch pc to perform calculations, comparisons, and checks on each stored input message.
Program instructions for computers are stored in electronic memory units. Some programs need to store some input data for future reference or future processing. Similarly, output instructions may be delayed or stored before being transmitted to the system's execution unit.
Vehicle-mount computers use two types of random access memory: volatile and non-volatile memory. All data in volatile memory is lost when the ignition switch is turned off. The memory can be directly connected to the battery via a wire to avoid data loss after the ignition switch is turned off. Both temporary memory and KAM have the disadvantage of losing stored data when the power is lost. The program-controlled radio is an example, when the battery is disconnected, all band settings are lost. All band information is stored in random access memory, and the band must be re-set when reconnected to the battery. System fault codes are usually stored in random access memory, which can be erased by disconnecting the battery.
Vehicle mount touch computers process input signals and send voltage signals or instructions to other devices in the system. The computer can send signals to the dashboard to give the driver information. It can also send signals to the engine control module to let the engine computer know about the working condition. And it can send signals to actuators to execute its decisions, quickly turn on and off equipment.
For example, the computer can quickly turn on and off fuel injectors and other devices, or keep the drive in a certain state for a certain period of time. We know that a driver is an electrical or mechanical device that converts electrical energy into mechanical motion. With a driver, the idle speed of the engine can be adjusted, the suspension height can be changed, or the air-fuel ratio can be adjusted to achieve output. Computers can also maintain contact or control with each other through their input and output functions. This means that through a computer network system, the output signal of one computer can be used as the input signal of another computer.
After the input signals of various sensors on the car are converted into digital signals, the vehicle-mount computer can understand and use the meanings represented by these signals, turn on and off various output devices that control engine operation, and achieve functions. Vehicle-mount computers will be a necessary device for future cars, and in the near future, cars are likely to be the products with the most embedded computers.
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