When defining a header file, you often
#ifndef _sys_h
#define _sys_h
.............
#endifWhy not define it this way?
#ifndef sys.h
#define sys.h#endifWhat does the short dash mean?...
After I connected the TX line of ATmega8 and the TX line of AT89C52 microcontroller, the signal sent by AT89C52 was pulled high. Has anyone encountered such a situation? How to solve it? Note: I used ...
With the rapid development of science and technology, especially the widespread application of digital technology and various ultra-large-scale integrated circuits, electronic equipment, especially...[Details]
As a wireless broadband metropolitan area network standard, WiMAX technology has greater advantages than previous 3.5GHz MMDS products in terms of non-line-of-sight transmission and spectrum utiliz...[Details]
This paper designs a dot matrix LED text display screen that is easy to update, expandable, and low-cost. The way to reduce costs is
① Use the Bluetooth data transmission function of mobile ph...[Details]
I. Introduction
Since RS232 has a short communication distance (only 15 meters according to EAT/TAI-232 standard), and can only perform point-to-point communication, it cannot directly f...[Details]
1 Introduction
PROFIBUS is an international, open, and manufacturer-independent fieldbus standard. It is widely used in manufacturing automation, process industry automation, and automatio...[Details]
PV inverter manufacturer SMA has launched its first DC arc fault circuit interrupter (AFCI) PV inverter and has received UL certification.
The new SunnyBoy AFCI inverter models include 3000-US...[Details]
Digital array radar (DAR) uses digital beam forming (DBF) in both receiving and transmitting modes to achieve flexible distribution and reception of RF signal power in the airspace, obtain excellent t...[Details]
TC9012F is a universal CMOS large-scale integrated circuit for infrared remote control signal transmission, suitable for remote control of TV, VTR, laser player and other equipment. In the market, ...[Details]
introduction
MAX6636 is a multi-channel precision temperature monitor that can not only monitor local temperature, but also connect up to 6 diodes externally. Each channel has a programmable...[Details]
Spatial Division Multiplexing (SDM) MIMO processing can significantly improve spectrum efficiency and thus greatly increase the capacity of wireless communication systems. Spatial Division Multip...[Details]
LED light sources have many environmental advantages, but early products still have certain technical bottlenecks in heat dissipation and high brightness design that cannot be broken through....[Details]
Liquid crystal display (LCD) panels have a wide range of applications, from small portable electronic devices to large fixed devices, including digital cameras, laptops, personal data assistants, d...[Details]
0 Introduction
Under normal circumstances, the three-phase power in the power system is symmetrical, and they meet certain amplitude and phase conditions; but when the load changes, the syst...[Details]
When the so-called "copycat phones" that flood the domestic mobile phone market move towards large screens, stereo amplifiers, touch controls, and even GPS navigation and mobile TV, the homogeneity...[Details]
1 Introduction to LED
With the development of science and technology, people have higher and higher requirements on automobile light sources. LED (Light Emitting Diode) has gradually attracted...[Details]