Recently, I made a functional driver for a USB device, analyzed its speed bottleneck, and found out the main reasons that affect the speed of the device. Because of the versatility of the USB device, the Code subject directly uses the sample code provided by DDK: bluckusb.1. USB dr
. As far as I understand it now, the USB drive is divided into two pieces, a USB bus driver, this thing, the Linux kernel has been done, we can ignore, but we must at least understand his function. The image must say, the USB bus drive is equivalent to paving a road, so that all the information can be reached through t
~1, first of all your mobile hard drive to support USB3.0. The words. Just look at the parameters of the hard drive below and you'll know.2, a support USB3.0 data cable. Now the new mobile hard drive standard will be included with one, the distinction method can be referred to in the 3rd Step (2).3, your computer needs to have the USB3.0 interface. How to differentiate the USB3.0 interface? There are actually 2 ways:(1) The simplest and most intuitive way is through the color of the
AT91 USB Composite Driver Implementation1. Introduction The USB Composite device is a general-to-integrate, or more functions-to-one single Device.It is defined in the USB Specification Revision 2.0, as "A device which has multiple interfaces controlled independently of Each of the other ".This document introduces basi
few states, you need to know what USB devices are, and so on.The second step is to peep the whole picture;How does a USB device work? In fact, the USB subsystem is a sub-level work, they cooperate with tacit understanding, do their own part of the matter, everything to the overall situation. USB drive can be divided i
USB mouse as an example. The USB Host Control continuously requests the USB mouse. The request interval is very short. The binterval field in the endpoint descriptor specifies that when the mouse experiences an event, the Mouse sends the data back to the host.Host Control interrupts the CPU, so usb_mouse_irq is called. In usb_mouse_irq, the data sent from the mo
Win10 after the update, Bluetooth function is gone, there is no option to open the Device Manager, there is an unknown USB device, reboot invalid, reload Bluetooth driver is invalid, Bluetooth in the BIOS is open.Try to find all the methods on the Internet, including Update WIN10 update, update Bluetooth driver, etc. are not resolved,Solutions are:1. Open the Dev
round check protocol. When a device needs to send data to the master controller, the master controller must notice and send a request to the device that wants to send the data. That is, the USB device does not need to interrupt the master computer in the traditional way, but provides the interrupt endpoint, and the host periodically checks the interrupt endpoint
Driver Standard enhanced PCI to USB host Controller each boot has a yellow exclamation point, USB interface is not available, each time you have to manually uninstall the Device Manager Standard enhanced PCI to USB host Co Ntroller, and then the scan is installed properly. B
one, Linux under the USB driver
Separation and tiering is the most basic form of driver development in Linux, USB drive development in the host side mainly involved in two parts: Host controller driver and device
In the previous article, I think everything about USB is clear, and her connection method is clear, so I will study the USB system structure. Let's take a look at the topological structure of the system.
Host Controller and a root hub. Then, you can connect many devices or connect to the hub. Then, you can connect to the device under the hub, connect to the next
, indicating that the network card is connected. If not, you can use the next method.NIC driver installation is successful, still unable to connect networkThree configuration networks (optional)The reason is that there is no configuration eth0, click here http://blog.csdn.net/iycao/article/details/22497291 have a workaround.This article is for reference, thanks to the following sources:CentOS Installation: http://blog.sina.com.cn/s/blog_86e874d30101e3
way. Plug-and-play, no need to install additional drivers, just install the driver of the printer. The driver settings of this printer are also very simple
1. Make sure that the printer and computer are connected.
Connect the printer to the computer using a USB interface (WINXP System) on my computer, right-click, choose Properties, choose hardware, choose D
the kick_khubd function, add the current hub to the Hub driver queue hub_event_list, and then wake up the hub daemon wake_up (khubd_wait) to start parsing what happened to the hub.
3. After hub_thread is awakened, It will be executed and hub_events will also be executed.
4. hub_events is the main function used to analyze hub events. The content of hub analysis is executed here. This function is a large endless loop.
5. hub_events processing process
5
Platform: mini2440Kernel: Linux 2.6.32.2When the USB device is plugged in, the kernel reads the device information, and then compares the information in the id_table with the information read to see if it matches and, if so, calls the probe function. The disconnect function is called when the USB device is unplugged. The URB is used in USB device drivers to descr
Execute PS-A | grep khubd on the terminal, and the khubd process is displayed. This is the hub daemon process. Our device is inserted into the USB interface (whether it is inserted with the hub, after the sub-hub), the daemon detects the issue and then notifies the master controller of the interruption. The master controller then calls the hub detection function
The workaround is as follows:
1. confirm the USB Cable whether there are more than 3 meters, the standard length is 1.5 meters, whether there is a transformer, If so, it is recommended to replace the standard data cable.
2. Replace other USB interface test for PC.
3. Check to see if the printer driver is properly driven.
4. Check the
A. Core Module Usbcore ------> corresponding Kernel configuration parameter config_usb B. USB master controller driver module Ehci_hcd (EHCI) USB 2.0 supports ------> config_usb_ehci_hcdUhci_hcd (uhci) PC system chip support ------> config_usb_uhci_hcd Ohci_hcd (OHCI) Non-PC system chip support------> Config_usb_o
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