SenkyLaser various types of laser radar sensor provides a rich interface signal, the customer when the choice is not clear what kind of signal for themselves, often cause a lot ofThe use of impact. Now make a column on various signal interface for customers according to their own needs to choose the appropriate signal interface.

UART serial communication

UART stands for Universal Asynchronous Receiver/Transmitter, which is a module/chip used for serial communication. UART module has built-in sending and receiving circuits, which can realize asynchronous serial communication with serial port devices.

Advantages:

1. Strong universality: The UART communication protocol is a universal asynchronous serial communication protocol, which is often used for the communication between the single chip microcomputer chip and peripheral devices.

2. No clock synchronization is required: The UART uses asynchronous communication. That is, no clock synchronization is required before data transmission.

3. Long transmission distance: Low level of electrical signal of UART is 0V, high level is 3.3V or 5V, and low level can be transmitted for a distance of several hundred meters.

4, simple data transmission: UART communication data can only be transmitted one bit at a time, the communication rate is not high, but the simplicity of data transmission is a non-negligible advantage.

5. Duplex communication: UART supports full-duplex communication, that is, data can be transmitted and received at the same time.

Disadvantages:

1. The data transmission rate is relatively low, usually in the range of thousands to hundreds of thousands of times per second, suitable for short-distance communication.

2. Low reliability. Since UART represents binary digits by using a level voltage difference, this means that its signal strength weakens with distance, which often leads to signal loss or damage.

3. Easy to be interfered. The asynchronous communication between two communication parties is often easy to be interfered, and the data transmission may be wrong or lost.

4. Limited data length: The UART can only transmit one bit at a time, which limits the data length and requires multiple transmissions to complete data transmission.

Generally speaking,UART is a universal serial communication protocol, which has the advantages of strong universality, but it also has the disadvantages of low communication rate and low reliability, so it should be selected according to the actual demand.

IIC

The Inter-Integrated Circuit (IIC) interface, also known as the 120 interface, is a serial communication interface protocol used to transfer data between integrated circuits (ics). The 1IC interface was developed by Philips in 1982 to simplify the complexity of connecting multiple ics while reducing the number of cables and connection costs.

The main features of the IIC interface include:

1, serial transmission: using two wires (SCL and SDA) for two-way serial data transmission.

2. Multi-host architecture: It allows multiple host devices (such as CPU, DSP, FPGA, etc.) to communicate with each other through 1IC bus.

3. Master/Slave device mode: On the 11C bus, the device can be a host or slave. The host device controls the communication on the bus, and the slave device responds to the control instructions of the host device.

4. Data frame structure: Data transmission through variable data length (up to 256 bytes) and optional validation mechanism. A data frame consists of the start bit, slave device address, read/write bit, ACK bit, data bit, and stop bit.

The 11C interface is suitable for many applications, such as peripheral control, sensor reading, memory reading and writing, communication protocols, etc. Because of its low power consumption, simple implementation and reliability, become Xu. One of the standard interfaces for multiple embedded systems and microcontrollers.

Advantages:

1. Two-way transmission: 11C can be used for two-way data transmission through the same wire, reducing the number of connection lines and saving space.

2. Multi-device connection: Multiple devices can be connected together through the 11C bus to realize data exchange at any time.

3. Automatic address assignment: When the device is connected to the bus, the address is automatically assigned without manual setting.

4. Power saving: The transmission rate of 11C is low, and the maximum transmission rate can only reach 400 Kbps, so its power consumption is relatively low. 5. High reliability: The 11C uses two-way transmission and verification mechanism, which can detect and correct errors in the process of data transmission.

Disadvantages:

1. Slow transmission rate: The maximum transmission rate is only 400 Kbps. In large data transmission scenarios, the transmission rate is slow.

2. Line length limitation: 11C requires linear level conversion through resistance, resulting in line length limitation. Excessive cable length may cause communication failure.

3. Cable conflict: Multiple devices on the IIC bus share one SDA and one CLK cable. When multiple slave devices respond to requests at the same time, cable conflict may occur.

4. Address conflict: If multiple slave devices use the same address, address conflict may occur.

RS232

RS232 is a serial communication interface standard used to transfer data between data terminal equipment (DTE) and data communication equipment (DCE). RS represents RecommendedStandard in its name. 232 represents its recommendedstandard published in 1962. RS232 interface is a kind of early serial communication interface, which can only transmit one bit of data at a time by serial transmission. The standards of the RS232 interface define electrical and mechanical characteristics and define communication protocols between devices.

Advantages:

1. Transmission distance: RS232 interface can transmit up to 50 feet (15 meters), normal use of the distance of three to five meters, for most personal computers and other devices, perfectly adequate.

2. Speed: RS232 interfaces usually operate at low speeds, no faster than 115.2 Kbps, but in many application scenarios, this is sufficient.

3. Stability: RS232 interface is less sensitive to interference, and there is almost no bit error or other error in the transmitted data.

4. Universality: RS232 interface is widely used, many devices can realize data transmission through RS232 interface.

Disadvantages:

1. Relatively large space: the wiring of RS232 interface on PCB board needs corresponding space, which is larger than the popular USB interface, requiring higher wiring space and connector volume.

2. Excessive number of cables: RS232 connectors require 9-pin or 25-pin connectors and two pairs of cables are required. In the case of high speed and long distance communication, electromagnetic interference is easy to occur.

3. Hot swap cannot be implemented: Because the RS232 interface is a mechanical slot, it needs manual operation and does not support hot swap. In this case, you need to perform some operations on the device before inserting and removing it.

4. Rate limit: RS232 interface cannot meet the requirements of high-speed communication, and the general rate cannot exceed 115.2 Kbps, which has certain limitations in the real-time application of big data.

RS485

RS485 is a serial communication standard used to transmit data over long distances between multiple devices. It is an extension of RS232, which is suitable for communication in industrial fields and automation equipment. RS485 interface uses Differential Voltage to transmit information, which uses differential output to improve anti-interference and transmission distance, and can transmit data at a distance of 4000ft(1219m).

Advantages:

1. impedance matching: RS485 using differential signal transmission, impedance matching is better, conducive to reduce the impact of reflection, improve the transmission speed of the cable.

2. transmission distance: RS485 transmission distance can reach 1200 meters, suitable for long-distance communication, in the transmission distance, anti-interference and other aspects better than RS232.

3. multi-point communication: RS485 support multi-point communication, can be connected to multiple devices at the same time and communication, reduce the density and length of the communication line, reduce the system cost.

4. Anti-interference: RS485 transmission line for two pairs of lines, using differential signal transmission, noise and interference on its impact is small, with strong anti-interference ability.

Disadvantages:

1. rate limit: RS485 transmission rate is relatively low, generally less than 1Mbps, not suitable for high-speed data transmission.

2. Non-standard communication protocol: The communication protocol of RS485 is non-standard, and the communication parties need to agree on the data format and control information for transmission, which makes the communication between devices from different manufacturers relatively difficult.

3. Power failure: The RS485 port can be used only when the power supply is connected. Once the power supply is disconnected, communication cannot be performed.

4. easy to attack: Because the RS485 interface is a shared bus transmission, if no preventive measures are taken, it is easy to be hacked, resulting in confidentiality and data security issues.

RS422

RS422 interface is a widely used serial communication interface with the following characteristics:

1. Long signal transmission distance: RS422 interface can transmit data within a distance of 1200 meters, which is further than other serial interfaces.

2. High-speed transmission: The transmission speed of RS422 interface can reach 10Mbps, which can meet the needs of high-speed data transmission.

3. Two-way transmission: RS422 interface can support two-way transmission, that is, send and receive data at the same time.

4. Strong scalability: RS422 interface can support multi-point connection and connect multiple devices.

Advantages:

1. Long transmission distance: RS422 interface has a long transmission distance, which is suitable for long-distance transmission.

2. Fast transmission speed: The transmission speed of RS422 interface is fast, which can meet the needs of high-speed data transmission.

3. Support multi-point connection: RS422 interface can support multi-point connection, suitable for multi-device communication.

4. strong anti-interference ability: RS422 interface strong anti-interference ability, stable and reliable signal.

Disadvantages:

1. High cost: Compared with other serial interfaces, RS422 interface has a high cost.

2. lack of signal flexibility: RS422 interface sends and receives data signals lack of flexibility, is not suitable for the transmission of complex data.

3. Many signal cables: RS422 interface requires multiple signal cables for signal transmission, which occupies a large space.

CANBUS interface

CANBUS communication is a common bus communication protocol in distributed control system. It can realize the communication and coordination between multiple devices. It is usually used in the fields of automobile bus, industrial control, communication, entertainment equipment and so on.

Advantages:

1. High reliability: Because CANBUS communication protocol adopts differential signal transmission, communication interference and noise can be effectively reduced, thus improving the reliability of communication.

2. Strong anti-interference ability: CANBUS communication protocol can automatically detect errors in the process of data transmission, and resend or ignore error messages. Therefore, CANBUS communication has the advantage of strong anti-interference ability under strong noise and interference environment.

3. High transmission rate: CANBUS communication protocol supports high-speed data transmission with a transmission rate up to 1Mbps, so it is suitable for high-speed data transmission.

4. good scalability: CANBUS communication protocol has good scalability, can easily add new equipment, exchange data, etc., so as to realize the system upgrade and expansion.

Disadvantages:

1. For beginners, it is complicated to learn and implement the CAN communication protocol, so they need to have certain professional knowledge and engineering experience.

2. For uncontrollable data transmission,CANBUS communication protocol will affect the global communication quality, resulting in complicated global communication.

3. It takes a long time to start the system: CANBUS communication protocol requires system initialization and bus scanning, so it takes a long time to prepare when the system starts. In general, CANBUS communication is an advanced bus communication protocol, with high reliability, anti-interference, high transmission rate and good scalability, suitable for more complex industrial and traffic systems in the field of data communication.

4-20mA current analog signal

The 4-20mA analog signal is a form of signal widely used in the field of industrial automation control. It refers to the current signal, the current value of which varies between 4 and 20mA, corresponding to different values of the measured quantity.

Advantages:

1. Good anti-interference, stable and reliable transmission performance in industrial environment with large interference;

2. the transmission distance is long, up to hundreds of meters, and will not be affected by signal loss;

3. in the process of signal transmission, can make full use of the power supply in the wire and cable, no need to allocate power equipment;

4. Multi-channel transmission of multiple signals can be realized without configuration and calibration.

Disadvantages:

1. Slow transmission speed, compared with digital signal, its transmission rate is lower;

2. The hardware design is relatively complex, which requires the use of dedicated analog input/output interface design;

3. due to the influence of line resistance, wire length and other factors, it is necessary to control the signal strength during the design, otherwise the signal quality may be affected;

4. When 4-20MA signal is used, additional voltage-current conversion circuit is required, which increases the system cost.

Voltage analog signal

The 0-5V voltage signal interface is a common analog signal interface, which is usually used to transmit signals in analog scenarios. The working principle of 0-5V voltage signal interface is to convert analog signals into 0-5V voltage signals according to certain rules, so as to transmit them through the interface.

Advantages:

1. low cost: 0-5V voltage signal interface is usually implemented by the common analog circuit, so the manufacturing cost is relatively low, easy to use and promote.

2. Convenient and practical: 0-5V voltage signal interface usually has a high degree of standardization, a wide range of application scenarios, and can be connected with a variety of equipment interface, very convenient and practical.

3. the transmission distance is long: the voltage signal transmission distance is long, the signal distortion in the transmission process is small, will not have a big impact on the transmission measurement.

4. Simple installation and use: Because the 0-5V voltage signal interface is simple to use, easy to install and debug, for some non-professional users, easy to use.

Disadvantages:

1. Limited accuracy: there may be errors or distortion in the conversion process of voltage signal interface, so it will be limited by accuracy.

2. Slow data transmission rate: Because the 0-5V voltage signal interface belongs to analog signals, the data transmission rate is usually slower than that of digital signals.

3. by external noise interference: 0-5V voltage signal interface in the transmission process, may be subjected to electromagnetic interference, radio frequency interference and other external factors noise interference, which will affect the transmission and accuracy of data.

EtherNet

EtherNet interface is a standard interface for computer network communication, also known as Ethernet interface. It is commonly used in local area networks to communicate using the Transmission Control Protocol/Internet Protocol (TCP/IP) family of protocols.

Advantages:

1. High reliability: the EtherNet interface technology is mature, after a long time of development and improvement, has been very reliable.

2. Fast speed: The speed of EtherNet interfaces is very fast and can support high-speed data transmission, making multimedia applications and high-speed data transmission easier and faster.

3. Good flexibility: The design of EtherNet interfaces is very flexible, can be customized according to the actual needs of different network topology, transmission media and data transmission mode.

4. low cost: because EtherNet interface technology has been mature and widely used, so the cost is relatively low, making the application of cost sensitive applications can be more convenient.

Disadvantages:

1. Low security: Because EtherNet interface is a communication protocol based on public network, there is no high security.

2. Limited scalability: When you need to expand the network scale, the scalability of some interfaces may be limited. Therefore, you need to add new relay devices or replace network infrastructure.

3. Complex configuration: It is time-consuming and difficult, especially for novices, and it may take some time to learn and master related technologies.

4. Frequent interference: Because there are many interference factors between network devices within a certain range of cable distance, frequent interference problems may occur during long-term use.

Switching quantity IO signal

Switching quantity The IO signal is a digital signal indicating that there are only two states, namely on or off. It is often used to represent binary input or output states, such as the status of switches, buttons, sensors, indicators, and other devices. It is widely used in computer control system, industrial automation and machine control, such as the control of machine start-stop, subsystem switch, working state indication, etc. Switching voltage of IO signal is usually 5V or 24V, with high reliability, simple, easy to install, maintenance and so on.

IO interfaces are used to connect digital signals to external devices for communication between devices. In automatic control systems,IO interfaces are usually used to connect devices such as sensors and actuators, and communicate with controllers.

PNP and NPN are the two most common modes in IO interfaces. The difference is that the outputs are positive (+) and negative (-).

Advantages of PNP include:

1. Simple operation: thin oxide layer, good polarity judgment, easy to identify the installation direction.

2. good compatibility: PNP interface can be compatible with most of the digital circuit, and can meet the input characteristics of most of the digital circuit requirements.

3. wide range of application: PNP interface components are widely used in control and detection circuits, industrial automation and instrumentation industries.

Advantages of NPN include:

1. For some applications, the NPN IO interface can achieve higher precision.

2. with good voltage resistance, can deal with the high voltage environment.

3. It has high anti-interference ability and can run stably in complex environment.

Disadvantages of PNP include:

1. impedance instability: the output impedance of PNP IO interface is unstable, which will have an impact on the external circuit.

2. Complex circuit: the work involving multiple devices requires more circuit design;

3. Current output limitation: Because PNP IO interface is limited to output positive current, negative current output cannot be realized.

Disadvantages of NPN include:

1. Determine the sequence of signals: It seems difficult to determine the sequence of signals input by NPN IO interface.

2. Slow receiving speed: Because the input resistance of NPN IO interface is large, the receiving speed is slow.

In general, PNP and NPN IO interfaces have their own advantages and disadvantages, which can be selected and used according to the actual needs.