C5509A USB Remote Wake-up signal duration

Oliver Chen

Dear All,

According to the web page "USB made simple Part - 3 Data Flow" :

http://www.usbmadesimple.co.uk/ums_3.htm

It is also possible for a device with its remote wakeup feature set, to initiate a resume itself. It must have been in the idle state for at least 5ms, and must apply the wakeup K condition for between 1 and 15 ms. The host takes over the driving of the resume signal within 1 ms.

USB Device may issue 1ms~15ms K condition to Host as a signal for remote wakeup. The RWUP (Bit5) of C5509A's register USB Control Register (USBCTL) is for this purpose. However, it seems that there is not other register to control the duration of this signal.

As I encountered an USB compatibility issue, which may be solved by adjusting that duration, I'm wondering if I can adjust the duration of the remote wakeup signal issued by C5509A?

Regards,

Oliver

over 9 years ago

0 Sivaraj Kuppuraj over 9 years ago

TI__Mastermind 35645 points

Hi,

Team is working on and we will address your request shortly.

Thanks & regards,
Sivaraj K

0 Steve Tsang over 9 years ago in reply to Sivaraj Kuppuraj

TI__Mastermind 23785 points

Correct. RWUP bit is to tell the USB module to generate a remote wakeup condition on the bus. The specific wakeup signaling timing from the USB module is not programmable.

Regards.

0 Oliver Chen over 9 years ago in reply to Steve Tsang

Intellectual 725 points

Dear Steve,

OK, I understand. Thanks for your confirmation!

Regards,

Oliver

0 Oliver Chen over 9 years ago in reply to Steve Tsang

Intellectual 725 points

Dear Steve,

We found that the USB remote wakeup condition generated by C5509A lasts only 1ms, which seems result in compatibility issue on some PC. Knowing this period is not programmable, I'm wondering whether there is any other way to extend this 1ms period?

Regards,

Oliver

0 Steve Tsang over 9 years ago in reply to Oliver Chen

TI__Mastermind 23785 points

Have you consider adding external D-flop flop to extend the pulse?

Regards.

0 Oliver Chen over 9 years ago in reply to Steve Tsang

Intellectual 725 points

Dear Steve,

No... Since D+ & D- are bidirectional signals, I'm wondering whether it is possible to extend this pulse by adding a D-type flip-flop without affecting the normal USB function?

Regards,

Oliver

0 Oliver Chen over 9 years ago in reply to Oliver Chen

Intellectual 725 points

Dear Steve,

BTW, could you simply confirm C5509A's remote wakeup signal duration is actually 1ms or any other value? I guess maybe by checking TI's internal specification of that USB controller or Phy you can find this information.

Regards,

Oliver

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C5509A USB Remote Wake-up signal duration