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[email_address] Pradeep Patel USB
Agenda ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Motivation ,[object Object],[object Object],[object Object],[object Object]
Why USB ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
System Arch- north bridge/south bridge
Various USB devices ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Goals of USB2.0 ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
USB Specification (USB2.0) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
The USB Concept (Functional Overview) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
USB-- “Universal Serial Bus” ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Introduction ,[object Object],[object Object],[object Object],[object Object],[object Object]
Introduction…. ,[object Object],[object Object],[object Object],[object Object],[object Object]
Introduction… ,[object Object],[object Object]
Introduction… ,[object Object],[object Object],[object Object],[object Object]
Introduction ,[object Object],[object Object],[object Object],[object Object]
Advantages ,[object Object],[object Object]
Transfer Types in USB ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Transfer Types in USB (continued…) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
USB topology
Speed Identification (FS) ,[object Object]
Speed Identification  (LS) ,[object Object]
Speed Identification (HS) ,[object Object],[object Object]
USB Protocol layer ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Transaction (only token packet) Transaction (Token, data packet, Handshake)
USB Protocol layer (continued…) ,[object Object],[object Object]
Common USB Packet Fields   ,[object Object],[object Object],[object Object]
Common USB Packet Fields (Cont..) ,[object Object],[object Object],[object Object],[object Object]
USB Packet Types   ,[object Object],[object Object],[object Object],[object Object],[object Object]
Token Packets
Data Packets
Handshake Packets
Special
Logical organization of USB ,[object Object],[object Object],[object Object],[object Object],[object Object]
Endpoints
Endpoints (Cont..) ,[object Object],[object Object]
[object Object],[object Object]
[object Object],[object Object],[object Object],[object Object],[object Object]
Endpoint Types ,[object Object],[object Object],[object Object],[object Object],[object Object]
Control Transfers   ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Setup Stage ,[object Object]
Data Stage ,[object Object],[object Object]
Status Stage
Interrupt Transfers   ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Isochronous Transfers ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Isochronous Transfers (Cont..)  ,[object Object],[object Object]
Bulk Transfers ,[object Object],[object Object],[object Object],[object Object],[object Object]
Bulk Transfers   ,[object Object],[object Object],[object Object],[object Object],[object Object]
Bandwidth Management   ,[object Object],[object Object]
USB Descriptors   ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
USB Descriptors (Cont..)
Composition of USB Descriptors
Device Descriptors (Cont..)   ,[object Object],[object Object],[object Object],[object Object]
 
 
Configuration Descriptors ,[object Object],[object Object],[object Object]
 
Interface Descriptors ,[object Object],[object Object],[object Object]
Interface Descriptors
 
Endpoint Descriptors   ,[object Object],[object Object]
 
 
String Descriptors
All subsequent strings take on the format below
 
 
Bus Enumeration ,[object Object],1. The hub to which the USB device is now attached informs the host of the event via a reply on its status change pipe. At this point, the USB device is in the Powered state and the port to which it is attached is disabled. 2. The host determines the exact nature of the change by querying the hub. 3. Now that the host knows the port to which the new device has been attached, the host then waits for at least 100 ms to allow completion of an insertion process and for power at the device to become stable. The host then issues a port enable and reset command to that port.  4. The hub performs the required reset processing for that port. When the reset signal is released, the port has been enabled. The USB device is now in the Default state and can draw no more than 100 mA from VBUS. All of its registers and state have been reset and it answers to the default address.
Bus Enumeration (Cont..) 5. The host assigns a unique address to the USB device, moving the device to the Address state. 6. Before the USB device receives a unique address, its Default Control Pipe is still accessible via the default address. The host reads the device descriptor to determine what actual maximum data payload size this USB device’s default pipe can use. 7. The host reads the configuration information from the device by reading each configuration zero to n -1, where  n  is the number of configurations. This process may take several milliseconds to complete. 8. Based on the configuration information and how the USB device will be used, the host assigns a configuration value to the device. The device is now in the Configured state and all of the endpoints in this configuration have taken on their described characteristics. The USB device may now draw the amount of VBUS power described in its descriptor for the selected configuration. From the device’s point of view, it is now ready for use.
The Setup Packet   ,[object Object],[object Object],[object Object],[object Object]
The Setup Packet
Standard Device Requests
Standard Interface Requests
Standard Endpoint Requests
USB in Thermal Inkjet printers ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Links to USB information ,[object Object],[object Object],[object Object]
Format of Setup Data
Standard Device Requests
USB H/w & S/f
USB H/w & S/f
Host Controller Requirements  ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Host Controller Requirements … ,[object Object],[object Object],[object Object],[object Object],[object Object]
Hub ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Enumeration
Enumeration
UHCI Frame list
UHCI Frame list
[object Object]

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