[Q] Hierarchy and Structure of USB Functions in uPSD

byounghoon_koh · ‎2003-11-26

Posted on November 26, 2003 at 13:04

byounghoon_koh · ‎2011-05-17

Posted on May 17, 2011 at 11:56

Hello,

I'm investigating USB module of DK3200 Evalution Board. However I can't understand the module exactly. Would someone let me show the herarcy and structure of it?

I want to know the flow of Firmware and PC source for DK3200 Board in following situation.

1. When the DK3200 board is connected to a PC.

2. When PC application send read or write command to the DK3200 board.

Please let me know that!!

Best regards,

Byounghoon

[ This message was edited by: aormaniac on 22-11-2003 06:37 ]

petr23 · ‎2011-05-17

Posted on May 17, 2011 at 11:56

Hello,

1. When a USB device is attached, the host issues a reset signal. When the

reset signal is released, the USB device (uPSD) enters the unenumerated

state. Then the host performs a bus enumeration to identify the attched

device and to assign a unique address to it. The device responds to the

requests on its default pipe (endpoint0).

OnDeviceConfigured() is called from OnSetConfiguration() called from

OnSetupPacket() when SET_CONFIGURATION request is received (when the device

is in address state). ...

2. PC USB Host sends IN or OUT token (read or write request) to USB device.

Endpoint0 is bidirectional for all data types, EP1 is IN type only

(direction to PC, refreshed by PC automatically in the selected time

intervals (x1ms) in the endpoint1 descriptor during configuration state).

When some IN token is sent to the device, USB interrupt service routine calls OnTransmitEP1() in case of EP1 .. etc.

Please read ''USB Demo App Structures.doc'' distributed with USB demo (C files directory) for detailed description ...

Regards,

Petr