Hi,

I am designing a USB 2.0 Device Controller with a UTMI interface,
assuming that I will be purchasing a PHY Chip which is UTMI compliant.

My question is about how the device knows if it is connected to the USB
hub/port. The answer I presume is that the device checks the V+ line
and if powered assumes that it is connected.

In my case my device controller connects via the UTMI interface to the
PHY....unfortunately there is no signal comming out of the PHY which
signals a device connect or a power up. ( absence of ..say..power-on
reset).

I need to know this point of device connection as I must send a reset to
my device logic and also reset the PHY.

Another way of asking the same question would be ,
With reference to the UTMI 1.0 Specifications on Page 52 , where does
the device_reset signal come from ?

Hope to get some clarification.

Regards
Kingfischer.

Hi, The UTMI interface is intended for USB2.0 peripherals only and not the device/host controllers. For details refer to http://www.usb.org/developers/onthego/ and search for ULPI/UTMI+ Regards, Neelabh In UTMI specs the timing kingfischer@rediffmail.com wrote:

Hi Kingfischer, If you are using the standard UTMI interface then it has a 2 bit output called LineState. This signal replicates the actual DP and DM lines. When the device gets attached, the pull - up on DP line will be connected to Vcc thus, producing a J state on the DP - DM lines. This state gets replicated on the LineState signal of the UTMI which tell the device that it has got connected. I hope this explanation answers your question. Regards, Virendra. kingfischer@rediffmail.com wrote: Hi, I am designing a USB 2.0 Device Controller with a UTMI interface, assuming that I will be purchasing a PHY Chip which is UTMI compliant. My question is about how the device knows if it is connected to the USB hub/port. The answer I presume is that the device checks the V+ line and if powered assumes that it is connected. In my case my device controller connects via the UTMI interface to the PHY....unfortunately there is no signal comming out of the PHY which signals a device connect or a power up. ( absence of ..say..power-on reset). I need to know this point of device connection as I must send a reset to my device logic and also reset the PHY. Another way of asking the same question would be , With reference to the UTMI 1.0 Specifications on Page 52 , where does the device_reset signal come from ? Hope to get some clarification. Regards Kingfischer. _______________________________________________ http://www.opencores.org/mailman/listinfo/usb Yahoo! India Matrimony: Find your partner online. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.opencores.org/forums/usb/attachments/20041123/704fbe61/attachment.htm