biometric driver

Character Device Driver: 1. Generally, we use APIs that dynamically allocate device numbers: Int alloc_chrdev_region (dev_t * Dev, unsigned int firstminor, unsigned int count, char * Name ); Dev is a function used for output. After successful call, the first number of the allocated range will be saved. Void unregister_chrdev_region (dev_t first, unsigned int count ); The above function allocates device numbers for

Android Deep Exploration ( volume 1) HAL with Drive Development Chapter I Android system porting and driving development Overview reading notesThis chapter isAndroidsystem porting and Driver development Overview of the specific explanation. First,Androidis divided into four layers of architecture. At the bottom of it isLinuxkernel. And then, respectively,C + +code Base,Android SDK Aand applications. andAndroidtransplantation is also divided into syste

Laptop installed sound card driver error no appropriate Driver to be installed Cause Analysis: There are Realtek and conexant two kinds of sound cards, when the system can not automatically identify the device when there will be an error. Solution: Enter the corresponding folder double-click Setup to install the driver If Realtek's sound card enters the

1, create a device node in the/sys/class/directory, such as creating a CLASS_TEST_USB device node[CPP]View Plaincopy Static struct CALSS *test_class; Test_class = Class_creat (This_module,"Class_test_usb"); 2, create another device node in the CLASS_TEST_USB directory android0, as follows[CPP]View Plaincopy struct device *dev; dev = device_creat (Test_calss,null,mkdev (0,0), NULL,"android0"); if (Is_err (dev)) return Ptr_err (dev); 3, create severa

The driver Microsoft Print to PDF required for the printer is unknown. Before logging on, please contact the Administrator to install the driver ., Microsoftprintpdf After this problem occurred, I felt very confused because the printer was not installed on the server. Where did the printer come from? Through Baidu search, I found a post on the Internet to answer my questions. Original post address: http:/

This is a creation in Article, where the information may have evolved or changed. Problem:2015/12/04 17:03:36 sqldb.go:2166:sqldriverconnect: {IM005} [MICROSOFT][ODBC Driver Manager] driver Sqlallochandle on SQL_ HANDLE_DBC failure Environment: Go language writingSQL SERVER DatabasePackages used by the "CODE.GOOGLE.COM/P/ODBC" database operation The program just started, running all right, but after a perio

I. Linux USB driver levels 1. devices, configurations, interfaces, and endpointsThe logical organization of a USB device consists of four layers: device, configuration, interface, and endpoint. A device usually has one or more configurations: Each USB device provides different levels of configuration information, which can contain one or more configurations, different Configurations enable devices to exhibit different combinations of functions (

Kernel: Implementation Process of request_irq (riq, handle, irqflags, devname, devid ); Overall idea of Interrupt driver and Application Design: Driver code implementation process:Third_drv.c # Include Application code implementation process:Thirddrvtest. c #include

Access control is sometimes critical for the reliability of a device node. This part of content is only modified on the open and release methods, and some check mechanisms are added. Exclusive Device The most rigid access control method is to allow a device to be opened (exclusive) by a single process at a time, which is the simplest access control for a device driver. The implementation is very simple. For specific code, see the experiment source co

USB connection mode installation drive: 1, put the drive CD into the computer optical drive, and then open the disc, and then pop-up window we select "I have read and accept this License agreement", click Next, as shown in the following figure: 2, the following interface we selected "USB": 3, check the "software and utilities to install", and then click Next Action: 4, click "Advanced Options"-"Browse" This is to replace the driver installat

This article allows reprint, please specify the source:Http://blog.csdn.net/fulinusThe Linux kernel code is too big, a small module will let you unprepared, this afternoon resolved to take the SPI drive a good look.First analyze the spidev.c file, which defines the members in the struct file_operations structure. Members have Spidev_write, Spidev_read, and Spidev_ioctl, and the first two implement half-duplex communication, which implements full-duplex communication. Of course there are open and

ifeq (Some of them are common or we have seen, the first oneIfneq ($ (kernelrelease),)at present, it is useful to refer to the origin ofLinuxunder the source root directoryMakefilewhen compiling the kernel,Kernelreleasemacros are defined, so if you start from the source root directory Makeit will behello.oThe module is compiled into the kernel. KERNELDIR: =/ home/zp1015/desktop/linux-2.6.32.2 kerneldir Assignment, This variable is used to refer to the kernel source directory that we used l

, length *//* Source: One of the endpoints of the USB device */Pipe = Usb_rcvintpipe (dev, endpoint->bendpointaddress);/* Length: */Len = endpoint->wmaxpacketsize;/* Purpose: */Usb_buf = Usb_buffer_alloc (Dev, Len, gfp_atomic, usb_buf_phys);/* Use "3 features" *//* Assign USB request block */Uk_urb = usb_alloc_urb (0, Gfp_kernel);/* Use "3 feature settings Urb" */Usb_fill_int_urb (uk_urb, Dev, pipe, usb_buf, Len, Usbmouse_as_key_irq, NULL, Endpoint->binterval);UK_URB->TRANSFER_DMA = Usb_buf_phys

What if the driver installation fails? If you want to use 91 assistants to give you a mobile phone to install the driver, we have to open the phone's USB debug option to here also to introduce another method: mobile phone installed 91 help 1, install a apk in the handset, then open the handset "WLAN" switch, simultaneously in the computer and the handset all runs "91 assistants". 2, then

A WiFi module was used in the recent project, the master being mt7612u, and the USB interface. Use of Linux version 2.6.35, in the process of compiling the driver encountered a lot of problems, especially in this record. Get the source MTK official website Drive. Contains Windows, Linux, and drivers under the Mac. I modified the GitHub drive. Add a new platform In the source code built some hardware platform configuration information, if not suitable

This question toss for a long, old thought is MySQL drive problem, fortunately finally found that El expression is not recognized${snapshot}"Problem:"-//sun Microsystems, INC.//DTD Web application 2.3//en""Http://java.sun.com/dtd/web-app_2_3.dtd" >The 2.3 version used by the servlet does not support El expressions by default, and the workaround is to add a sentence to the pageJSP page cannot use JSP cause MySQL driver cannot find "java.sql.SQLExceptio

Environment: Operating system: 64-bit WIN7 database: SQL Server SP1 Development language: Java EE Error prompting when Servlet connects to database: [Microsoft] [ODBC Driver Manager] in the specified DSN, the architecture between the driver and the application does not match Workaround: Upgrade SQL Server SP SP1 to SQL Server # SP SP4 o

The BS System Using C # + ODBC has no problem in vs2005, but it will appear after it is released"Error [im002] [Microsoft] [ODBC driverProgramManager] No data source name found and default driver not specified"Error, the problem is that the type created by DSN is incorrect. In "ODBC data source Manager", you can set three DSN types for connecting to the database: User DSN, system DSN, and file DSN. IIS is a system-level NT Service. Therefore, you ca

I. Some preliminary knowledge 1. You have been able to write led bare-board drivers.Program 2. convert a physical address to a virtual address In the program, we can only use the converted virtual base address and register offset to access the corresponding register, instead of directly accessing the physical register as the bare board program, so the physical address must be converted, the following is an example. # Include Void _ iomem * vir_base; vir_base = ioremap (gpio_base, gp

To reinstall ODBC, follow these steps: Use odbcconf.exe to re-register the ODBC driver. There are several script files in the Windows/system32 directory to complete the driverProgramRegistration: Odbcconf.exe/S/LV odbcconf. log/F % SystemRoot % \ system32 \ mdaccore. RSPOdbcconf.exe/S/LV odbcconf. log/F % SystemRoot % \ system32 \ sqlclnt. RSPOdbcconf.exe/S/LV odbcconf. log/F % SystemRoot % \ system32 \ odbcconf. RSPOdbcconf.exe/S/LV odbcconf. log/