USB device is not recognized (LPC3250)

"Now while debugging, I see the USB_GetDescriptor function is invoked and the valid vid and pid host registry Enum too..along with, a vid and pid 0 enum is registered."

host registry? - Are you debugging your Windows application or the board?

"Now while debugging, I see the USB_GetDescriptor function is invoked and the valid vid and pid host registry Enum too..along with, a vid and pid 0 enum is registered."

host registry? - Are you debugging your Windows application or the board?

There is no windows application. Of-course device driver.

host registry: -In windows registry, currentcontrolset->enum->usb

device is LPC3250
host is windows

while the application is running/debugging on device and the usb cable is connected!!!!

"There is no windows application. Of-course device driver."

You're asking questions about the LPC3250. Don't you think it would be more valuable doing some debugging of that side?

Yes it is Debugging on device side only, using uvision and ulink2ICE

and when the cable is connected, i get in the USB_GetDescriptor (where I set the breakpoint) and I see USB_DeviceDescriptor (which is having vid and pid) is send back to the host from device.

these settings i am able to see in the host registry toooooo.
device manager doesnot reflect this.

Ok. So we've now established what you're actually debugging.

You say your evaluation board has an ISP1301, but have you confirmed that it is being accessed correctly? Is the I2C address as expected by the example code?

Have you now checked the startup code to ensure that it is enabling all the necessary devices on the board correctly - Including the SDRAM.

Is the memory layout of your evaluation board the same as expected by the example code?

These are questions you should have answers to. In answering those, you might find the a difference that is causing your board to fail. I can confirm that I got the basic example code working on our custom board, with only minor tweaks.

Thanks for the replies IB Shy,
I have made it work.

I have been struggling to get USB Host configured on the Phytec Board (with a different OS & Compitler). I have confirmed the ability to configure the ISP1301 and clocks appear to be correct.
I have configured the LPC3250 USBHost controller in DAT/SE0 bi-directioanl mode to the point that it queues Transfer Buffers, but the D+/D- lines never toggle on the scope. Each transfer subsequently results in a "No Device Response" condition code.

Do you have a code fragment that configures USBHost that you can share? Or possibly just register dumsp of the relevant USB register?