收藏本站
1
Chapter 1
1-2-2 PIPES
A USB pipe is a logical association between an endpoint and a software structure in the USB
host software system. USB pipes are used to send data from the host software to the
device’s endpoints. A USB pipe is associated to a unique endpoint address, type of transfer,
maximum packet size, and interval for transfers.
The USB specification defines two types of pipes based on the communication mode:
■
Stream Pipes: Data carried over the pipe is unstructured.
■
Message Pipes: Data carried over the pipe has a defined structure.
The USB specification requires a default control pipe for each device. A default control pipe
uses endpoint zero. The default control pipe is a bi-directional message pipe.
1-2-3 TRANSFER TYPES
The USB specification defines four transfer types that match the bandwidth and services
requirements of the host and the device application using a specific pipe. Each USB transfer
encompasses one or more transactions that sends data to and from the endpoint. The
notion of transactions is related to the maximum payload size defined by each endpoint
type in that when a transfer is greater than this maximum, it will be split into one or more
transactions to fulfill the action.
CONTROL TRANSFERS
Control transfers are used to configure and retrieve information about the device
capabilities. They are used by the host to send standard requests during and after
enumeration. Standard requests allow the host to learn about the device capabilities; for
example, how many and which functions the device contains. Control transfers are also
used for class-specific and vendor-specific requests.
A control transfer contains three stages: Setup, Data, and Status. These stages are detailed in
Table 1-1.
18
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
AD637-EVALZ BOARD EVALUATION FOR AD637
AD736-EVALZ BOARD EVALUATION FOR AD736
AD737-EVALZ BOARD EVALUATION FOR AD737
AD8007AKS-EBZ BOARD EVAL FOR AD8007AKS
AD8018ARU-EVAL BOARD EVAL FOR AD8018
AD8034ART-EBZ BOARD EVAL FOR AD8034ART
AD8040AR-EBZ BOARD EVAL FOR AD8040AR
AD8045ARD-EBZ BOARD EVAL FOR AD8045ARD
相关代理商/技术参数
AD-UCUSB-HCCDC-SPL 制造商:Analog Devices 功能描述:?C/USB HC CDC FOR CCES SINGLE PROD LIC - Virtual or Non-Physical Inventory (Software & Literature)
AD-UCUSB-HCMSC-SPL 制造商:Analog Devices 功能描述:?C/USB HC MSC FOR CCES SINGLE PROD LIC - Virtual or Non-Physical Inventory (Software & Literature)
AD-UCUSBH-MCDC-SPL 制造商:Analog Devices 功能描述:MAINTENANCE ?C/USBH CDC SINGLE PRD LIC - Virtual or Non-Physical Inventory (Software & Literature)
AD-UCUSBH-MHID-SPL 制造商:Analog Devices 功能描述:MAINTENANCE ?C/USBH HID SINGLE PRD LIC - Virtual or Non-Physical Inventory (Software & Literature)
AD-UCUSBH-MMSC-SPL 制造商:Analog Devices 功能描述:MAINTENANCE ?C/USBH MSC SINGLE PRD LIC - Virtual or Non-Physical Inventory (Software & Literature)
AD-UCUSBH-SPRD 功能描述:PRD LIC UCUSB DEV CORE CCES SGL 制造商:analog devices inc. 系列:CrossCore? Embedded Studio 零件状态:在售 类型:- 应用:- 版本:- 许可长度:- 许可 - 用户明细:- 操作系统:- 配套使用产品/相关产品:Blackfin? 处理器 媒体分发类型:- 标准包装:1
ADUM1100 制造商:AD 制造商全称:Analog Devices 功能描述:iCoupler Digital Isolator
ADUM1100AR 功能描述:IC DIGITAL ISOLATOR 1CH 8-SOIC RoHS:否 类别:隔离器 >> 数字隔离器 系列:iCoupler® 产品培训模块:IsoLoop® Isolator 标准包装:50 系列:IsoLoop® 输入 - 1 侧/2 侧:5/0 通道数:5 电源电压:3 V ~ 5.5 V 电压 - 隔离:2500Vrms 数据速率:110Mbps 传输延迟:12ns 输出类型:CMOS 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SOIC N 包装:管件 工作温度:-40°C ~ 85°C 其它名称:390-1053-5