On 11 4 ,   2 23 , karthikbalaguru <karthikbalagur...@gmail.com>
wrote:
> On Nov 2, 4:49 pm, Bin Chen <binary.c...@gmail.com> wrote:
>
>
>
> > Hi,
>
> > I am debugging s3c2410's usb device driver for linux, I have connect
> > the VCC, GND, D+, D- and the usb device end can detect the insert/plug
> > of usb cable. I installed a IRQ handler for the usb device and it can
> > recieve some interrupt of reset when I insert the USB to host.
>
> > But after the reset, no further interrupt happen. Even in the host
> > side there are nothing displayed. I want to know how can I debug it?
>
> > According the USB spec, after the HOST hub send Reset to device, the
> > device need to pull up/down a data line to indicate the existence of
> > the device, can I measure this signal on the four lines? Which line
> > should I measure?
>
> > I think the host didn't begin to enumerate the device because the
> > device didn't send ACK of the reset to indicate the attach.
>
> Which version of USB are you using ? USB 1.1/USB 2.0.
>
1.1

Bin Chen <binary.chen@gmail.com> wrote:

>Hi,
>
>I am debugging s3c2410's usb device driver for linux, I have connect
>the VCC, GND, D+, D- and the usb device end can detect the insert/plug
>of usb cable. I installed a IRQ handler for the usb device and it can
>recieve some interrupt of reset when I insert the USB to host.
>
>But after the reset, no further interrupt happen. Even in the host
>side there are nothing displayed. I want to know how can I debug it?
>
>According the USB spec, after the HOST hub send Reset to device, the
>device need to pull up/down a data line to indicate the existence of
>the device, can I measure this signal on the four lines? Which line
>should I measure?
>
>I think the host didn't begin to enumerate the device because the
>device didn't send ACK of the reset to indicate the attach.

There are flow charts in appendix C of the USB spec that show the reset
handling, and the text is in section 7.1.7.5.
-- 
Tim Roberts, timr@probo.com
Providenza & Boekelheide, Inc.

On Nov 2, 4:49 pm, Bin Chen <binary.c...@gmail.com> wrote:
> Hi,
>
> I am debugging s3c2410's usb device driver for linux, I have connect
> the VCC, GND, D+, D- and the usb device end can detect the insert/plug
> of usb cable. I installed a IRQ handler for the usb device and it can
> recieve some interrupt of reset when I insert the USB to host.
>
> But after the reset, no further interrupt happen. Even in the host
> side there are nothing displayed. I want to know how can I debug it?
>
> According the USB spec, after the HOST hub send Reset to device, the
> device need to pull up/down a data line to indicate the existence of
> the device, can I measure this signal on the four lines? Which line
> should I measure?
>
> I think the host didn't begin to enumerate the device because the
> device didn't send ACK of the reset to indicate the attach.
>

Which version of USB are you using ? USB 1.1/USB 2.0.

Karthik Balaguru

Hi,

I am debugging s3c2410's usb device driver for linux, I have connect
the VCC, GND, D+, D- and the usb device end can detect the insert/plug
of usb cable. I installed a IRQ handler for the usb device and it can
recieve some interrupt of reset when I insert the USB to host.

But after the reset, no further interrupt happen. Even in the host
side there are nothing displayed. I want to know how can I debug it?

According the USB spec, after the HOST hub send Reset to device, the
device need to pull up/down a data line to indicate the existence of
the device, can I measure this signal on the four lines? Which line
should I measure?

I think the host didn't begin to enumerate the device because the
device didn't send ACK of the reset to indicate the attach.

Thanks.
Bin