Dear All, When a device starts HNP, did it drive vbus all the time? Did it still drive VBUS to supply power even after its role transfer from a_host to a_peripheral? If the description has misunderstanding, please refer to attach file. Thanks lot! __________________________________ Do you Yahoo!? Yahoo! Mail - Easier than ever with enhanced search. Learn more. http://info.mail.yahoo.com/mail_250 -------------- next part -------------- A non-text attachment was scrubbed... Name: hnp.JPG Type: image/jpeg Size: 54282 bytes Desc: hnp.JPG Url : http://www.opencores.org/forums/usb/attachments/20050111/cdfe274d/hnp-0001.jpg

Hi Xianshic, Hnp can be initiated by B Device. but the HNP is enabled by A Device with a control Transaction. After getting enabled the B Device will have capability for becoming HOST. The Drive Vbus is always driven by A_Device only. It can drive Drvbus when A device become peripheral. Regards Ravikumar Krishnan -----Original Message----- From: xianshic [mailto:xianshic@yahoo.com] Sent: Tuesday, January 11, 2005 5:14 PM To: usb@opencores.org Subject: [usb] VBUS state in HNP Dear All, When a device starts HNP, did it drive vbus all the time? Did it still drive VBUS to supply power even after its role transfer from a_host to a_peripheral? If the description has misunderstanding, please refer to attach file. Thanks lot! __________________________________ Do you Yahoo!? Yahoo! Mail - Easier than ever with enhanced search. Learn more. http://info.mail.yahoo.com/mail_250