When using stm32F407 + lwip-1.3.1 communication without an operating system, suddenly the return value of udp sending data is always = ERR_IF; This ERR_IF is explained by an error in the underlying ne...
[font="][size=11.0pt]Almost every embedded device has a debugging serial port. In some scenarios, it is inconvenient to connect to the PC with a physical cable, and a wireless connection is required. ...
I am planning now,,, basically considering Beijing, Chengdu, Chongqing, Hunan,,, I am a Shanghai native,,,,,,,,, I have a house in Shanghai,,,,,,,,,...
We have a WinCE platform with Hive registry. Customers use the installation package to install software on the platform. During the installation process, the registry will be written, the relevant fil...
I have embedded LINUX and use a four-wire resistive touch screen. Now I have a problem. When I use the test program to read the value, the data of a certain area in the upper left corner of the touch ...
When using standby mode, the current is: 4uA (there are other backup clocks)When using stop mode (lower power), the current is: 118uA (there are other backup clocks)All the above modes use RTC.Accordi...
Assume that data is read from 8-bit AD (if it is a higher-bit AD, the data type can be defined as int), the subroutine is get_ad();
1. Limited secondary filtering
/* A value can be adjust...[Details]
In early 2002, I started to write a working program for an IC card prepaid electricity meter. The meter used Philips' 8-bit 51-expanded single-chip microcomputer
87LPC764
, and wa...[Details]
In
circuit design,
current
measurement
is widely used, and the main fields are divided into three categories: in measurement,
the electric meter
is used to measure the curre...[Details]
Floating-point digital signal processing has become a constant requirement for precision technology, often in applications requiring high accuracy in areas such as aviation, industrial machinery, a...[Details]
In this article, the high-performance DSP developed by TI can be used as an effective confidentiality method if it is applied to PC encryption cards.
As an effective network security solution,...[Details]
In public places such as schools, government agencies, factories and mines, as well as public corridors in residential areas, the phenomenon of long-burning lights is very common, which causes a h...[Details]
1 Introduction
Solar street lights are mainly composed of four parts: solar photovoltaic cell components, batteries, charge and discharge controllers, and lighting fixtures. The bo...[Details]
Contact resistance
is the resistance to current flow through a closed pair of contacts. This type of measurement is performed on devices such as connectors,
relays
, and switches. The...[Details]
1 Introduction to HART Protocol
HART (Highway Addressable Remote Transducer), an open communication protocol for addressable remote sensor high-speed channels, was launched by Rosemen in the U...[Details]
General LED lighting has a current limiting resistor in the driving circuit, and the power consumed by the resistor has nothing to do with the LED light emission. In order to improve efficiency, a...[Details]
Experimental tasks
A DS18B20 is used to form a temperature measurement system. The temperature measurement accuracy reaches 0.1 degrees. The temperature range is between -20 degrees and +50 de...[Details]
Overview
In spectral measurement, photomultiplier tubes (PMT) and charge-coupled devices (CCD) are often used as photoelectric converters. PMT is used in slow-changing, high-precision spectral...[Details]
Capacitance Measurement
Used to verify that capacitors meet the manufacturer's specifications. For quality control, a group of capacitors may be placed in an environmental chamber and the cap...[Details]
Continuity test
A variety of devices need to be checked for continuity, including cable assemblies, printed circuit boards, and connectors to ensure that these components have the expected contin...[Details]
At very low temperatures, certain metals and alloys lose their resistance to electric
current
and become
superconductors
. Two parameters that are often measured are the transition ...[Details]