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Rockbox mail archiveSubject: USB On-The-Go (OTG) (was: Re: 2nd ATA Device on JB20 Recorder)USB On-The-Go (OTG) (was: Re: 2nd ATA Device on JB20 Recorder)
From: Francesco Grassi <frangras_at_tin.it>
Date: Thu, 23 Jan 2003 00:25:58 +0100 Hi guys, I found these links: http://www.semiconductors.philips.com/buses/usb/products/otg/ http://www.semiconductors.philips.com/buses/usb/products/otg/tutorial/index. html [...] Point-to-Point Connectivity The OTG Supplement extends the USB standard to enable point-to-point communication between two USB devices: one OTG device and another OTG or traditional USB device. Because the two devices still maintain the roles of host and peripheral, OTG point-to-point communication is not to be confused with peer-to-peer. Unlike traditional USB, OTG allows only one peripheral at a time to be connected to the device acting as host. OTG devices do support USB hubs, a traditional way of enabling multiple USB peripherals to share a single USB host connection. However, some OTG functionality such as swapping host/peripheral roles and peripheral session requests are not supported across today's USB hubs. USB OTG device types range from battery-powered handheld products to non-portable peripherals. While initial device roles (host/peripheral) are defined by how they are cabled together, some OTG devices can switch roles through the host negotiation protocol (HNP) without changing the cabling. Figure 3: OTG enables point-to-point connectivity between peripherals without a traditional PC host. To better understand how new OTG devices and features add to existing USB functionality, a quick review of USB device terminology follows. The A-device is the default host at the start of a session. It supplies power to VBUS. The B-device is the default peripheral at the start of a session. To these, the OTG Supplement adds the OTG device and defines two types: a dual-role device and a peripheralonly device. [...] http://www.usb.org/developers/onthego/ Maybe it could be useful for our objective... FG -----Messaggio originale----- Da: owner-rockbox_at_cool.haxx.se [mailto:owner-rockbox_at_cool.haxx.se]Per conto di roland Inviato: mercoledì 22 gennaio 2003 23.35 A: rockbox_at_cool.haxx.se Oggetto: Re: 2nd ATA Device on JB20 Recorder jep, otherwise CF2IDE Adapters like these: http://www.flashmemory.com.au/shop/shopdisplayproducts.asp?id=3&cat=FlashMem ory+Disk+Drives would be a bit dangerous :) First I was unsure about this because I read contradictory comments - but at least http://www.compactflash.org/faqs/faq.htm#dvs approved that CF supports BOTH voltages. Regards Roland ----- Original Message ----- From: "Stuart Tedford" <stuart.tedford_at_piresearch.co.uk> To: <rockbox_at_cool.haxx.se> Sent: Wednesday, January 22, 2003 5:29 PM Subject: RE: 2nd ATA Device on JB20 Recorder > >-----Original Message----- > >From: Andrew Jamieson > > > >And dont forget that CF cards use 3.3V power, not 5V. > > No, CF cards allow for both 3.3 and 5V supply. > > Stu. > Received on 2003-01-23 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |