device

Device driver to act as a virtual web camera

只愿长相守 提交于 2019-11-30 04:05:10
I'm looking for writing virtual camera drivers. Does anybody has idea? Any book that would be helpful or any link. Adding more details: I have developed a device driver which saves the image to disk and the display uses the device driver to display the image. The performance does not seem good. The fns. that I have used are: //to capture GetDesktopWindow() CreateCompatibleBitmap() Save() //to display WM_MOUSEMOVE giving a call to capture and display every time but the display is not continuous and appears only after window goes out of focus and comes in focus again Should I use some other

Send IOCTL to Windows device driver - CreateFile fails

时光怂恿深爱的人放手 提交于 2019-11-30 03:17:47
问题 I want to send an IOCTL command to a PC/SC reader connected to my computer (win7 64 bit). In order to send an IOCTL command I need a HANDLE to the device, which I'm unable to create. The device is listed as "OMNIKEY 1021" in the device manager, the physical device object name is "\Device\USBPDO-15". Using the "WinObj" tool, I can detect 2 symlinks: USB#VID_076B&PID_1021#5&291f6990&0&1#{50dd5230-ba8a-11d1-bf5d-0000f805f530} USB#VID_076B&PID_1021#5&291f6990&0&1#{a5dcbf10-6530-11d2-901f

How does one determine the page frame number for device memory?

痞子三分冷 提交于 2019-11-30 03:17:36
问题 This question was migrated from Unix & Linux Stack Exchange because it can be answered on Stack Overflow. Migrated 7 years ago . From LDD3/ Ch. 15/ sections "Using remap_pfn_range" and "A Simple Implementation", pfn has been equated to the vm_pgoff field. I am confused by this. How can that be so? Note that vm_pgoff is described as: The offset of the area in the file, in pages. When a file or device is mapped, this is the file position of the first page mapped in this area. Thus if the first

Android Studio: what's causing logcat battery power supply logs?

六月ゝ 毕业季﹏ 提交于 2019-11-30 02:59:01
问题 I have an Android smartphone connected to my Mac using a USB cable. When running Android Studio, the following appears in the LOGCAT. These lines continually repeat, sometimes in a slightly different order. It's not clear to me what's causing this and how I can fix it... 08-09 16:17:31.554 2208-20167/? D/NetlinkSocketObserver: NeighborEvent{elapsedMs=11269730, 192.168.1.254, [5464D91A00EE], RTM_NEWNEIGH, NUD_STALE} 08-09 16:17:32.829 27970-27970/? E/NEW_BHD: Battery Power Supply logging

How to detect a mobile device manufacturer and model programmatically in Android?

假装没事ソ 提交于 2019-11-30 01:10:44
I want to find device specification of a mobile phone for examples, the device manufacturer, model no ( and may be types of sensors in the device, wifi chipset etc..). I want to get the device manufacture/model number (eg. Samsung GT-I9100 i.e Galaxy S2) programmatically. The manufacture/model number is also used in Google Play when installing an app. I want to use this information to make some configuration changes in my hardware dependent app (for eg. power measurement). You can get as below: String deviceName = android.os.Build.MODEL; String deviceMan = android.os.Build.MANUFACTURER; For

Qt programming: How to extend Javascript API in webkit

陌路散爱 提交于 2019-11-29 23:27:46
问题 I am new to Qt and what I am trying to do is: Create a Linux app using the Qt framework. This app displays some web pages from the Internet. I want to extend the JavaScript API to access some device and device based data, which means some devices can be controlled using JavaScript in Webkit. But how do I add some customized functions/classes to Webkit in Qt? 回答1: Fortunately, there exists some documentation on this, finally: http://doc.qt.io/qt-4.8/qtwebkit-bridge.html 回答2: I've done a

What triggers the BluetoothDevice.ACTION_ACL broadcasts?

筅森魡賤 提交于 2019-11-29 23:00:16
I would like to know what events in remote physical devices trigger ACTION_ACL_CONNECTED and ACTION_ACL_DISCONNECTED in a listening device. My test results make no sense. I have gathered several devices within a few decimeters of each other: a Galaxy Tab P7500 running Android 3.1 an i5500 phone running Android 2.2 a WinXP PC with a bluetooth USB dongle two headsets with on/off buttons First, I pair manually with all devices from the Tab. Neither the PC nor the phone are paired with any other device but the Tab. (One of the headsets can never be found by the tab in any way, but it can easily be

How to detect hardware keyboard presence?

最后都变了- 提交于 2019-11-29 22:59:43
Is there a way to detect if the device I'm currently running on has a hardware keyboard installed? How do I query device capabilities anyway? "The flags provided by getResources().getConfiguration().keyboard are a good way of checking which keyboard (if any) is available." [1] http://d.android.com/reference/android/content/res/Configuration.html#keyboard Use the following method to ascertain presence of hard keyboard at any time: (To my knowledge, soft keyboards all lack the features tested below ) public static boolean isHardKB(Context ctx) { Configuration cf = ctx.getResources()

How does Bluetooth pairing work?

荒凉一梦 提交于 2019-11-29 22:23:53
How exactly does Bluetooth paring work? What is communicated between each device during the pairing process? I was told if you had device-A wanting to pair with device-B : A sends a 'unique key' to device B on some wavelength/frequency B returns an 'echo' back to A , and hence the devices pair. +-----+ key +-----+ | | ----> | | | A | | B | | | <---- | | +-----+ echoed +-----+ This seems to be inaccurate, so would anyone be able to either expand further or actually explain how/what is communicated to result in a successful pairing of the devices? I was thinking of incorporating some of this

Android Virtual Device ERROR on Android Studio

十年热恋 提交于 2019-11-29 22:12:17
问题 When I try the open Virtual Device, I see the same error. What can I do? That error : Emulator: warning: host doesn't support requested feature: CPUID.80000001H:ECX.abm [bit 5] I can't fix my problem :/ I asked yesterday but anyone answer it :/ Note : Virtualization Technology is enabled and KVM is OK. 回答1: This error is referring to CPU feature called LZCNT. It was introduced in Intel processors since Haswell (2013) and in AMD since 2007. So if your CPU is older or to any other reason does