ov51x_init_isoc in ov511.c usb_submit_urb[['s]] cause isoc transfer. for (n = 0; n < OV511_NUMSBUF; n++) { ov->sbuf[n].urb->dev = ov->dev; err = usb_submit_urb(ov->sbuf[n].urb); Lines as below in [hc_interrupt] show HcBufferStatus. //printk("bstat =%x hp->itl1_len=%d\n",bstat,hp->itl1_len); //printk("bstat =%x hp->itl0_len=%d\n",bstat,hp->itl0_len); You can find these sequence when capture image v(^o^) First usb_submit_urb set Second usb_submit_urb set HC set ITL0Buffer as these lines WRITE_REG16 (hci, hp->tlp, HcTransferCounter); WRITE_REGn16 (hci, HcITLBufferPort, hp->tlp, hp->tl); *After 1frame(1ms) isp1161 set ITL0BufferFull bit to 1 HC set ITL1Buffer *After 1frame(1ms) isp1161 set ITL0BufferDone bit to 1 isp1161 set ITL1BufferFull bit to 1 HC set ITL0Buffer *After 1frame(1ms) isp1161 set ITL1BufferDone bit to 1 isp1161 set ITL0BufferFull bit to 1 HC set ITL1Buffer > By the way, I found that the Tango version driver does some >extra work with ITL Buffer, it will write 0 to all those empty space >in the ITL Buffer, which is unnecessory and will influence its >performance. Sorry.I know it's not best way.[remove_urb in hc_simple_isp116x.c] If anyone have some idea.I hope somone try it. adsynori ------------------------------------------------------- This SF.Net email sponsored by Black Hat Briefings & Training. Attend Black Hat Briefings & Training, Las Vegas July 24-29 - digital self defense, top technical experts, no vendor pitches, unmatched networking opportunities. Visit www.blackhat.com _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel