Ten Daily Electronic Common Sense-Section 59

What are the main ways to receive SJAl000 messages?

Interrupt reception mode and query reception mode. The programming ideas of the two receiving methods are basically the same. If the real-time communication requirements are not very strong, it is recommended to use the query receiving method.

What are the commonly used arithmetic circuits?

In digital circuit design, arithmetic circuits are often involved. In addition to the adder circuit, there are many commonly used arithmetic circuits. Including subtractors, multipliers, dividers, trigonometric function calculators, Fourier transformers, etc. Among them, multipliers and dividers are the most typical.

What is network performance?

Network performance WirelessHART networks ensure high reliability through a variety of mechanisms. These mechanisms include: multiple paths to network equipment, multiple RF channels, and retransmission mechanisms. If higher network reliability is desired, additional routing paths can be formed by adding additional WirelessHART access points and WirelessHART field devices. Additional equipment increases the variety of paths. Additional WirelessHART access points and devices can also increase the throughput of the WirelessHART network, reduce latency, and be used for routing to bypass potential sources of interference.

What is the basic principle of the longitudinal current differential protection?

In the longitudinal current differential protection, current transformers with the same transformation ratio and the same type are installed on both sides of the line, and the polar ends of the current transformers at both ends are placed on the side close to the busbar.

What is OLEDoS?

OLEDoS is the abbreviation of silicon-based organic light-emitting display, which is a branch of active site-selective organic light-emitting display.

How to choose between an analog oscilloscope and a digital memory oscilloscope？

• If you need to choose between the two, it can be determined according to the signal to be observed.
  1. If you only look at some ordinary periodic signals. Such as sine wave, and the signal frequency is not high (MHz below), you can choose an analog oscilloscope. It is better than the digital oscilloscope in terms of price and actual observation effect, and the price is relatively cheap.
  2. If the observed signal is irregular, the frequency is very high. It also requires some data storage and data calculation. Such as the superposition calculation of multi-channel signals, FFT fast Fourier transform, etc., digital oscilloscope should be selected. Especially in the field of waveform precision measurement, recording and testing of various dynamic processes and transient response characteristics, measurement analysis in the field of radio communication such as coded communication signals. Especially in the measurement of intermittent signals, random signals, fast drift signals and ultra-low frequency signals, the advantages are obvious.

According to different analysis and display methods, what kinds of logic analyzers can be divided into?

According to different analysis and display methods, logic analyzers can be divided into two categories: Logic Timing Analyzer and Logic State Analyzer. The basic structure of these two types of analyzers is similar, and the main difference lies in the display mode and timing mode.

What is a sensor?

A transducer or sensor is a device that converts various non-electrical quantities (including physical quantities, chemical quantities, biomass, etc.) into another physical quantity (generally electricity) that is convenient for processing and transmission according to certain rules.

The application of intelligent sensor technology has improved the performance of medical instruments and equipment, mainly in what aspects?

1. Automatic data processing intelligent sensors have changed the traditional passive measurement of parameters into active measurement.
2. Self-detection, diagnosis and alarm function The intelligent sensor can detect whether the working state of the equipment is normal according to the preset algorithm, and can diagnose the root cause of the fault and display it in the form of fault code.
3. Interface function The intelligent sensor technology adopts standard digital output, and it is easy to realize the data exchange and sharing between the sensor and the system, and between the sensor and the network through the interface technology, forming a networked intelligent sensor system.

What kinds of finite state machines are classified according to their structure?

Divided into Moore-type state machine and Mealy-type state machine.