teleconference device

PCI device creation process This part is divided into two parts for learning. One is to refer to the previous articles, analyze the source code of ld1_and sculld, and the other is to refer to ldd3 to learn PCI. Part 1Ldd_bus declares the ldd_bus_type of a bus_type structure: Struct bus_type ldd_bus_type = { . Name = "LDD ", . Match = ldd_match, . Uevent = ldd_uevent, }; The code for adding ldd_bus_type to and detaching from the kernel is as follows:

USB Device cannot stop universal volume device resolution: Method One: Release clear off the clipboard Caused "Unable to stop the universal volume device", generally there are reasons, such as the above mentioned reason is the most common, the solution can be released to clear off the Clipboard, you can casually copy anything on the hard drive to release the co

The error is shown in the following figure Umdf hid MiniDriver device Unknown Device The reason may be that some external mouse, keyboard, camera, card reader, u disk or other USB device drivers should be automatically installed on the system but not installed successfully caused by, the following approach to see. 1. Locate the desktop computer, then righ

Before starting work, first in the PC to download the installation of the assistant, the installation is completed after the mobile phone connection computer, safe mobile end of the assistant; Connect iphone/ipad/ipod or other devices to the computer side's love-thinking Assistant The following diagram, the connection after the device jailbreak activation status, product type, serial number, production date warranty date, etc., can be seen; System

As there are too many notes in Chapter 10, I will post the previous notes first. 1. functions used to open various devices Device Function used to open a device File Createfile (pszname is the path name or UNC path name) Directory Createfile (pszname is the path name or UNC path name ). if you specify the file_flag_backup_semantics flag when calling createfile, Windows al

First, we know that the driver is part of the kernel, so what role does the driver play in the kernel?The role of the device driver in the kernel: they are separate "black boxes" that enable a particular hardware to respond to a well-defined internal programming interface that completely hides the work details of the device. (Plainly, the driver does not have any implementation details that are invisible to

Tag:linux drive Automatically create device node #include Linux device-driven implementation automatically creates device nodes

(I2C_DEV_FD {printf ("Standard_i2c_read standard_i2c_open failed\n");Goto _over_;}IOCTL (i2c_dev_fd,i2c_timeout,1);/* Timeout time */IOCTL (i2c_dev_fd,i2c_retries,2);/* Repeat Count */ E2prom_data.nmsgs=1;e2prom_data.msgs= (struct i2c_msg*) malloc (e2prom_data.nmsgs*sizeof (struct i2c_msg));if (!E2PROM_DATA.MSGS){Perror ("malloc error");Goto _over_;} Reg_buf[0] = (register_addr >> 8) 0xFF; E2prom Data Address 16bitREG_BUF[1] = register_addr 0xFF; E2prom Data AddressREG_BUF[2] = pbuffer[0]; Wr

2.1Network Driver StructureThe architecture 1 of the Linux Network Driver is shown in.It can be divided into four layers:(1) Protocol Interface Layer (2) network device interface layer (3) Device Driver Function Layer (4) network device and media layer. Network Driver Focus: completes the device driver Function Layer I

Reason:Is that the virtual machine service is not turned onWorkaround: (Run as Administrator)Click "Start → run", enter CMD in the Run box to open a command prompt, then execute the following command in turn.net start VMCInet start vmx86net start Vmnetuserifsc config Vmci=autosc config Vmx86=autosc config Vmnetuserif=autoVMware cannot open the kernel device "\\.\global\vmx86": the system cannot find the file specified. Have you rebooted after installi

Now, let's write our own first character device driver--light LEDs. (Imperfect, back to perfect) Hardware platform: Exynos4412 (FS4412) Writing the drive is divided into the following steps: A--View the schematic, data manual, understand the equipment operation method; B-Find a similar driver in the kernel, develop it as a template, and sometimes need to start from scratch; C-Implement driver initialization: For example, register the driver with the

Failure phenomenon: When the WIN10 system uses a PIN to log on, it sometimes prompts "your device is offline, please log in with the last password used on this device." Solution: This time need to connect the network, re-enter the password to log in, you can connect to the wired network or wireless network, the following describes the connection network solution. 1. Click on the wireless i

When debugging, it is found that there is no selected device or the selected device Xcode does not support: Workaround: 1. Download the DMG you need on the Internet to find out if you have any https://pan.baidu.com/s/1pLoxkDH?errno=0errmsg=Auth%20Login%20Sucess. bduss=ssnerror=0traceid= #list/path=%2f 2.Finder Click "Apps" to find Xcode, right click to select "Show Package Contents" and go to "Con

Turn off eclipse. Turn Adb.exe off in Task Manager Enter the ADB directory and then execute the ADB start-server to successfully execute the problem resolution 　　The problem should be solved, but if adb start-server start up!Finally, the reason for the port occupancy is found.Here's how to fix it:1.adb nodaemon serverTo view the reasons that cannot be performed, output: Cannot bind ' tcp:5037 ' 2. Fixed a problem with the port! Yes, Port 5037 is occupied!3.netstat -ano | findstr

How to use the device tree of linux drivers and how to use the device tree of linux drivers The Device Tree describes the hardware from the software perspective, and DTS is the Device Tree source file. DTC is responsible for converting DTS to DTB, and DTB is the binary form of DTS for machine use. The