My Linux is Ubuntu, and I can't get into root. I looked at /etc/shadow and found the following:Can any experts please tell me how to solve this? Thank you!...
[table] [tr][td][size=3][color=#000][font=宋体]Ultraviolet LED lamp beads, 1W high power and low power SMD LED lamp beads, please recommend manufacturers with good price and quality, as well as driver p...
I am a novice, just contacted with STM, recently there is a project to use STM8 to directly drive the stepper motor (without subdivision driver) for two weeks. Although the motor can run and accelerat...
The hardware used is CH423, 3.3V voltage, pull-up 4.7K, 33pF capacitor filtering
When testing I2C, I found that there was a step in NACK. What caused this?...
As LEDs continue to improve in almost every aspect of performance and cost, LED lighting is being used in an increasingly wide range of applications, among which LED street lights are a focus of in...[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]
From the PIC16F946 datasheet, we know that there are two ways to write values to the LCD for display:
1. Directly write the value to LCDDATA1~LCDDATA23
2. Use disconnect t...[Details]
Instrument stepper motor
The stepper motor is an open-loop control element that converts electrical pulse signals into angular displacement or linear displacement. In the case of non...[Details]
1. What is temperature?
Heat is a type of molecular motion. The hotter an object is, the faster its molecules move. Absolute zero is defined as the temperature at which all molecular motion ...[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]
Printed circuit boards ( PCBs
)
are used in most electrical products
. If a PCB has low
insulation resistance
(IR), the performance of the circuits on the PCB will be greatly reduced...[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]
D5026A is a driver IC designed by Shanghai Debei Electronics for energy-saving LED display screens. Its design concept is energy-saving and compatible with existing solutions, that is, it can be ...[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]
Only a small number of LED manufacturers can produce high-quality LEDs. For applications that are only used for simple indication, low-quality LEDs are sufficient. However, high-quality LEDs must...[Details]
0 Introduction
High-precision current source can provide high-precision current supply for precision instruments, and is suitable for automatic measurement tasks of various resistors in semico...[Details]
The serial interface real-time clock chip DS1302 launched by Dallas Company in the United States can trickle charge the backup battery of the clock chip. Due to the main features of the chip such a...[Details]
1. Introduction
With the increasing popularity of fully automatic washing machines, consumers have higher and higher requirements for their environmenta...[Details]
With the rapid development of cities and the improvement of citizens' living standards, the number of various vehicles in cities is growing, and the demand for parking spaces in major commercial an...[Details]
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