if(down_interruptible(&dev->sem)) return -ERESTARTSYS; dev->sem is a semaphore used to implement mutual exclusion. What do these two lines of code mean? Because down_interruptible normally returns 0, ...
Error[e104]: Failed to fit all segments into specified ranges. Problem discovered in segment CODE. Unable to place 77 block(s) (0x1cec byte(s) total) in 0x754 byte(s) ofmemory. The problem occurred wh...
1. Overview
Will passive devices
produce nonlinear intermodulation distortion? The answer is yes! Although there is no systematic theoretical analysis, it has been found in engineerin...[Details]
1 Introduction
A wide variety of communication cables and control cables are widely used in various instruments and control equipment. Whether the cable is well-conducted and
whether
th...[Details]
0. Introduction
In daily life, we often see some special-purpose vehicles. When these vehicles pass through intersections, they often obtain the right of way at intersections by temporarily op...[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]
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]
1 Introduction
Intelligent control instruments are one of the most commonly used controllers in industrial control. They are mainly aimed at a specific parameter (such as pressure, tempera...[Details]
MediaTek (2454) announced the acquisition of F-MStar (3697) and attracted the attention of IC design industry. This morning, Gartner Semiconductor Industry Research Director Hong Cenwei analyzed ...[Details]
Among the many members of the single-chip microcomputer family, the MCS-51 series of single-chip microcomputers has occupied the main market of industrial measurement and control and automation eng...[Details]
From the previous section, we have learned that the timer/counter in the microcontroller can have multiple uses, so how can I make them work for the purpose I need? This requires setting the timer/...[Details]
With the widespread application of new services and technologies in the communications industry, the scale and capacity of operators' network construction are getting larger and larger, and the ris...[Details]
Introduction
X1226 has the functions of clock and calendar. The clock relies on hour, minute and second registers to track, and the calendar relies on date, week, month and year registers to tr...[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]
At present, a large number of cooling tower fans, speed fans and special fans are in use in petroleum, chemical, pharmaceutical, metallurgical and other enterprises. Some fans have no monitoring in...[Details]
Introduction
Today, as IC (integrated circuit) has developed to a super-large scale, IC design based on IP (Intellectual Property) cores and their reuse are important means to ensure the ef...[Details]
Zarlink Semiconductor has developed an ultra-low-power RF transceiver chip for pacemakers, neurostimulators, drug pumps, and other such implantable medical devices. It has high data rates, low power c...[Details]