android headphone volume

Android sound focus ---- adjust the volume of Music from Music back to Luncher Sound types are defined in the AudioSystem. java file. /* The default audio stream */public static final int STREAM_DEFAULT = -1;/* The audio stream for phone calls */public static final int STREAM_VOICE_CALL = 0;/* The audio stream for system sounds */public static final int STREAM_SYSTEM = 1;/* The audio stream for the phone r

By learning Android Deep Exploration (Volume one) HAL and Driver Development Chapter Sixth let me understand the complete process of developing and testing Linux drivers for counting the number of words.The Linux system maps each driver into a single file, which is called a device file or driver file, and is stored in the/dev directory. Since most Linux drivers have their corresponding device files, exchang

By learning Android Deep Exploration (Volume one) HAL and Driver Development eighth chapter Let me know how to make the Development Board sound, how to write a buzzer driver. Understand the code reuse of Linux drive, code reuse is divided into static and dynamic two kinds.Linux-driven code reuse there are many ways, you can use the standard C program, the code of the important code in other files, if you wa

By learning Android Deep Exploration (Volume one) HAL and Driver Development chapter Tenth let me know the debugging technology and debugging tools for embedded Linux.PRINTK can print kernel debugging information, the function is similar to the printf function, except that the PRINTK function runs in kernel space, and the printf function runs in user space. The PRINTK file is a simple four-digit text file w

file system (/dev). /proc is a virtual file system, which means that/proc is not a real file system, but a memory map.Debugging Tools:Debug the user space program with GDB, remotely debug the user space program with Gdbserver, and debug the kernel program remotely with KGDB.When you find that there are too many bugs in a piece of code, it is difficult to find out through the PRINTK function output information, consider using KGDB to locate the bug in step by step mode.Read "

Linux drivers is very important, is to modify the Linux driver source code, should try not to modify the Linux The driver interface. In a complete Linux Drive, mainly consists of internal processing and hardware interaction two parts. If the inter-Linux porting between different versions , the main porting of the first part, on different hardware platforms, then the main second part. Software 1308 class 31st Zhang Fan Blog Park address: http://home.cnblogs.com/u/sxauzzz/

extinguished. The ARM processor has multiple registers, by setting the values of different registers. You can set the status of the LED PIN, open or disable the pull-up (pull-up) circuit, and control the light and off of the LEDs.4. Control LEDLED drivers can use the following two ways to control LEDs:The LED is controlled by a string,Control led by l/0 command;To control LEDs, use both of these methods. The LED driver must receive the corresponding data. If the LED is controlled by a string. Y

The reason was not found, but it seems to be resolved as follows:Resolution process: Because the code is very small, so I re-establish a blank program, copy the code in the past, the word is not bad. Recompile, the key moment is up: Do not connect to the real machine, when the compilation is complete, the system prompts whether to launch the Android emulator, select "No", this time to exit. To the bin directory to see, the program size from the origin

S3C6410 is a low-power, cost-effective SC (reduced instruction set computer, introduced by Samsung,Compact instruction set computer processor, which is based on the ARM11 kernel.OK6410 Development Board with "core board + backplane" structureInstall serial debugging tool: MinicomFirst step: Detect if the current system supports SB-turn serial portLsmod | grep usbserialStep Two: Install Minicomsudo apt-get install minicomStep Three: Configure Minicomsudo minicom-sEntering the "Serial Port Setup"

provides a branching concept. In other words, the person participating in the development creates a branch for each modification so that the commit does not affect the code of the main branch after the modification.Local branches are designed to isolate changes to different parts of the main branch. Use the git checkout command to switch between different local branches. It is meaningless if you only operate locally.Using Git to manage your source code will use a remote git hosting server. GitH

uninstallationStep two: Register and unregister the device filesCreate and remove device files using the misc GI mis dere ter function, respectively.Step three: Develop something related to the driveMOD ule_a uthormodule CE SE MOD ULE LI MODUL DES ript IO macros can specify driver-related information.Fourth step: Specify the callback functionA driver does not have to specify all the trap functions. The callback function is registered through the relevant mechanismFifth step: Writing business lo

1. Select the icon to add to the cart from http://www.iconfont.cn/.2. Select the download code in the shopping cart.3. Open the compressed package and put the four files in the package into the Asstes folder in the project.4. Import the picture in the code by setting TextView typeface.1 TextView TestView = Findviewbyid (r.id.text); 2 Typeface Typeface = Typeface.createfromasset (Getassets (), "Iconfont.ttf"); 3 Testview.settypeface (typeface); 4 Testview.settext (html.fromhtml (" #xf0343;")); Te