Ten Daily Electronic Common Sense-Section 69

What is COS?

COS (chip operating system) is developed around the characteristics of the smart card it serves.

What are the units of commonly used Resistors?

Resistors have sizes, which are often described in conjunction with numbers and units. As mentioned earlier, the resistance value of a resistor is “500”, where “50” is the quantity and “Ω” is the unit. Ω is the basic unit of resistance, but this unit is too small in electrical engineering. In practice, it is often necessary to use a degree much larger than Q, such as kΩ, MΩ, GΩ, and TΩ. Their relationship is as follows: 1TΩ=1000GΩ; 1GΩ=1000MΩ; lMΩ=1000kΩ: lkΩ=1000Ω. With this relationship, TΩ, GΩ, MΩ, kΩ, and Ω can be converted into each other. If the resistance value of a resistor is “4700f2”, then this resistance value can be abbreviated as “4.7kΩ” or “4.7k”.

What is the color conversion method?

The color conversion method is also called the color conversion method or the blue light CCM process method. The method is to use the blue light emitted by OLED to absorb light with dyes and then transfer the three primary colors of red, green and blue.

How does the basic UART communicate?

The basic UART communication only needs two signal lines (RXD, TXD) to complete the mutual communication of data, and the reception and transmission are in the form of full duplex. TXD is the UART sending end, which is the output; RXD is the UART receiving end, which is the input. There are two states on the signal line, which can be distinguished by logic 1 (high level) and logic 0 (low level). When the transmitter is idle, the data line should remain in a logic high half state.

What are the aspects of embedded debugging?

Embedded debugging includes hardware debugging, software debugging, and simulation debugging. Monitor debugging is a monitoring program that mainly receives the control commands sent by the host, parses them, and executes them on the target. Then some results and status of the target machine are fed back to the host machine. In the debugging and development provided by EPSON, Monitor debugging provides two forms: Hard Monitor debugging, that is, using hardware to complete the monitoring function; Soft Monitor debugging, that is, using a monitoring program to complete the monitoring function. Simulation mode (Simulator). The target machine is not required, and the host machine can simulate the environment of the target machine and run the program that should be executed on the target machine. This is only a verification of the logical function. Under normal circumstances, in the debugging of the embedded system, the simulation debugging is carried out first, the logic verification of the user program is carried out, and then the online simulation debugging is carried out to carry out the simulation verification of the actual environment.

What are the two basic forms of data distribution for the electronic control unit on the CAN bus?

• The first form is proactive release by set or need.
• The second form is posted upon request.

What is a separate terminal?

This is a termination configuration method that enhances EMC performance without changing the DC characteristics of the termination cable.

Compared with general computer network systems, what are the characteristics of fieldbus?

1. Strong reliability and fault tolerance.
2. The real-time requirements are high. In some cases, the discreteness of the information transmission delay is small or the time of the network event is determined.
3. The message length is small and the transmission delay is small.
4. Low cost and simple structure.
5. The ability to adapt to the environment is strong, and it can work in harsh environments.
6. The degree of standardization is poor, and the network interconnection ability is poor.
7. The data transmission speed is low.

How to train the debugging staff? What is the training content?

• In order to carry out the debugging work smoothly, the debugging personnel should carefully study the drawings, the factory test report of the equipment manufacturer and the relevant technical data, understand the layout of the field equipment, and be familiar with the wiring of the relevant electrical system. Before debugging, you must understand the functions of various electrical equipment and the entire electrical system, and master the methods and steps of debugging.
• The commissioning personnel must be familiar with the structure, operating procedures and working requirements of the electrical system of the controlled equipment before commissioning. As an installation and commissioning personnel, you must first understand the technological process and control process of the entire equipment, and then understand the drawings; then compare the drawings, first check the internal wiring of the equipment as a whole (in fact, refer to the drawings and compare the actual wiring); To be proficient in the various instruments used on the equipment being debugged.
• Learn how to first aid people who have been electrocuted.

How to design FPGA/CPLD circuit?

The process of FPGA/CPLD circuit design refers to the process of developing and designing FPGA/CPLD devices using EDA tool software on the computer. It generally includes seven steps of design preparation, design input, functional simulation, design implementation, timing simulation, download programming and device testing.