USB Complete fourth- P23 ppt

... devices, FTDI Chip’s FT232R USB UART introduced in Chapter 6 provides a quick way to upgrade a design to USB. The chip can con- vert an existing RS-232 device to USB with minimal design changes ... modules are available to enable connecting to a PC via USB. Devices with other functions may require redesigning for USB. The device might use the WinUSB driver or a generic or custom drive...

Ngày tải lên: 04/07/2014, 07:20

... should use a USB interface? Find out whether your device should use USB or another interface. If the choice is USB, you’ll learn how to decide which of USB s four speeds—including USB 3.0’s SuperSpeed—and ... other USB devices? Find out how to develop a host for an embedded system or a USB On-The-Go device that can function as both a USB device and a limited-capability host tha...

Ngày tải lên: 04/07/2014, 07:20

... the host in response to the next Get Port Status request. A USB 1.x hub may instead detect the device’s speed just after a bus reset. USB 2.0 requires speed detection before the reset so the hub ... bandwidth. To help ensure that devices will enu- merate without problems, default interfaces in USB 2.0 and USB 3.0 devices must request no isochronous bandwidth. In other words, a default...

Ngày tải lên: 04/07/2014, 07:20

... way to provide this information, the Wireless USB specification introduced two new descriptor types. The USB 2.0 Link Power Management Addendum and USB 3.0 specifi- cation also incorporate these ... return no string descriptors must not return an array of lan- guage IDs. The USB- IF’s website has a list of defined USB language IDs. bString is valid for string descriptors one and high...

Ngày tải lên: 04/07/2014, 07:20

... high-speed USB boards with EZ -USB chips: the USBee EX2 Experimenter’s Board from CWAV, Inc. and the QuickUSB Module from Bitwise Systems, Inc. Both boards contain programmed Cypress EZ -USB FX2 controllers, ... that handles non -USB tasks and communicates with the USB controller as needed. These chips are sometimes called USB interface chips to distinguish them from microcontrollers...

Ngày tải lên: 04/07/2014, 07:20

... fit a defined USB class and need only bulk or isochronous transfers. #TEJKVGEVWTG FTDI’s chips take a different approach to USB design. The controllers handle enumeration and other USB communications ... enables adding USB to just about any CPU circuit. A disadvantage is the need to use two chips instead of having the CPU and USB controller on a single chip. Also, example code for...

Ngày tải lên: 04/07/2014, 07:20

... (hiddev.inf in Windows 98) hub usb. inf mass storage usbstor.inf printer usbprint.inf smart card smartcrd.inf still image sti.inf Chapter 9 236 the example, this value is USB\ VID_0925&PID_1456. ... and protocol codes and may have any of the following forms: USB\ Class_aa&SubClass_bb&Prot_cc USB\ Class_aa&SubClass_bb USB\ Class_aa The values aa, bb, and cc match values i...

Ngày tải lên: 04/07/2014, 07:20

... Definitions public const string WINUSB_DEMO_GUID_STRING = "{42CA71EC-CE1C-44c2-82DE-87D8D8FF6C1E}"; Use System.Guid myGuid = new System.Guid( WINUSB_DEMO_GUID_STRING ); 4GSWGUVKPIC2QKPVGTVQC&GXKEG+PHQTOCVKQP5GV The ... object. 8$ Definitions Public Const WINUSB_DEMO_GUID_STRING As String = _ "{42CA71EC-CE1C-44c2-82DE-87D8D8FF6C1E}" Use Dim myGuid As New Syst...

Ngày tải lên: 04/07/2014, 07:20

... to a PC’s serial port via RS-232 or a USB/ COM-port adapter. The firmware writes debugging data to the serial port for display by the USBwatch application. USBwatch can display enumeration and ... exchanging data with attached and enu- merated HIDs (except system mice and keyboards). USBwatch is a low-budget USB analyzer for HIDs. To use the analyzer, you add the provided code to your Chap...

Ngày tải lên: 04/07/2014, 07:20

... vendor-specific functions is Microsoft’s WinUSB driver. This chapter shows how to develop a device that uses the WinUSB driver and how to use the WinUSB API to access the device from applications. %CRCDKNKVKGUCPF.KOKVU A ... the device from applications. %CRCDKNKVKGUCPF.KOKVU A device is a candidate for using the WinUSB driver if the device and its host computer(s) meet the requirements b...

Ngày tải lên: 04/07/2014, 07:20