USB port reset

[omury]

Posted on August 08, 2006 at 12:39

USB port reset

[omury]

Posted on August 08, 2006 at 07:22

Hi.

I want to reset USB port without unplugging and re-plugging cable. I tried to setting FRES and PDWN bits in USB_CNTR register. I also tried to PowerOff() function in usb_pwr.c but they are not working. How can I make the PC re-recognize my USB STR711 device?

Thanks

yusuf

[anis23]

Posted on August 08, 2006 at 08:03

Hi Jozef,

To generate an USB reset from device point of view you have to disconnect and re-connect the pull-up resistor (on the D+ line).

You have to provide a schematic to disconnect this resistor using a GPIO pin.

Please find attached a simple example of schematic able to connect and disconnect the pull-up resistor using one GPIO, two transistors and three resistors.

Regards,

AnisAs :D

________________

Attachments :

USB_reset.bmp : https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006HtPS&d=%2Fa%2F0X0000000aPb%2FpjMKRLzxLvsHrUpPyWagUYfxL3uRU.sMdyIYh06wT_U&asPdf=false

[omury]

Posted on August 08, 2006 at 12:39

Hi AnisAs,

Thank you for your urgent reply. It's working!!!

regards

yusuf