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Message
From: naikvs@m...<naikvs@m...>
Date: Wed Mar 17 18:19:54 CET 2004
Subject: [usb] USB-to-Bluetooth
Hi,
I am looking for a Bluetooth module which should sit on to my target USB
host port. Is there any bluetooth module which comes with USB interface
for the embedded applications.
Let me know the availabe modules.
Thanks & regards,
Venkatesh S Naik
L&T Emsys,Mysore
Karnataka,India-570018
Phone No:+918212402561
----- Original Message -----
From: "Ricky Nite" <ricky@h...>
To: <usb@o...>
Date: Fri, 14 Feb 2003 11:47:03 +0800
Subject: Re: [usb] USB-to-Bluetooth
> Hello Marc,
>
> I get your point, thanks - it really doesn't make sense to make the
> USB-to-Bluetooth adapter look like a hub. It just has to look like
> a
> typical USB device that communicates with the upper layers of
> the Bluetooth stack and application running on the PC/host.
>
> However, this would mean that I would have to define a separate
> USB bus for each peripheral device, because I cannot use the
> USB port of the device to make a similar Bluetooth Dongle
> connection as I did on the PC/host. I will have to reconfigure the
> Dongle as host, which, as I've been told, requires a lot of
> resources
> and is not supported by existing Dongles.
>
> Is there any other way to do this? Or maybe this is one of those
> applications that's just "not meant to be" :) In that case, I won't
> use the upstream USB port anymore - I'll just use the downstream
> USB port on my host/PC to attach the Dongle, and Bluetooth-enable
> all my peripherals...
>
> Ricky Nite
>
> ----- Original Message -----
> From: Marc Reinig
> To: usb@o...
> Sent: Thursday, February 13, 2003 10:13 PM
> Subject: RE: [usb] USB-to-Bluetooth
>
> Because of the turn-around time (and some other issues), you cannot
> just convert transmissions from the PC host and send them to the
> device on the other side of the Bluetooth net (and vice versa)
> because the Bluetooth protocol will not be able to respond in time
> for the USB protocol requirements. So, the USB device must "dummy"
> up responses from the remote Bluetooth device until actual
> responses are received. This requires extra horsepower at the USB
> dongle end. Same issue for the USB-to-Bluetooth adapter to act as a
> hub.
>
> In any case, the USB is just a bus to attach the Bluetooth adapter
> to the PC Host, Bluetooth can already accept multiple connections,
> what would be the function of trying to make the USB-to-Bluetooth
> adapter look like a hub?
>
> Marc Reinig
> System Solutions
>
>
> -----Original Message-----
> From: owner-usb@o... [mailto:owner-usb@o...]On
> Behalf Of Ricky Nite
> Sent: Wednesday, February 12, 2003 11:13 PM
> To: usb@o...
> Subject: Re: [usb] USB-to-Bluetooth
>
>
> Hello Marc,
>
> Thanks for the reply - so a USB-to-Bluetooth Adapter
> is just another USB device as seen by the PC , but I'm
> still wondering what you meant with a "smart" USB
> device (?)
>
> I'm also trying to find out if it's possible for the PC-attached
> USB-to-Bluetooth adapter to emulate a hub, with the
> peripheral-attached adapters seen as slave devices (?)
>
> PC-->USB-BT adapter (hub)----->USB-BT adapters
> -->peripherals (slaves)
>
>
> Rgds,
>
> Ricky Nite
>
> ----- Original Message -----
>
> From: Marc Reinig
> To: usb@o...
> Sent: Thursday, February 13, 2003 12:31 PM
> Subject: RE: [usb] USB-to-Bluetooth
>
>
>
> -----Original Message-----
> From: owner-usb@o... [mailto:owner-usb@o...]On
> Behalf Of Ricky Nite
> Sent: Wednesday, February 12, 2003 7:17 PM
> To: usb@o...
> Subject: [usb] USB-to-Bluetooth
>
>
> > I need some clarification on Bluetooth-to-USB transmission.
> > As you know, some Bluetooth modules now have an on-chip
> > USB interface, used for device firmware upgrade and as HCI
> > transport. Future Bluetooth firmware upgrades will also allow
> > you to change the USB descriptors in the module so you can
> > receive data over USB and transmit it over the air.
>
> > However, I was told that this will not allow me to layer
> additional
> > firmware over the embedded Bluetooth stack to do an exact
> > USB cable replacement using a USB-to-Bluetooth adapter/dongle
> > device, because:
>
> > (1) USB has strict timings which would be violated if the
> adapter/
> > dongle had to transmit the request over the air and wait for
> a
> > response.
>
> Correct, though this can be overcome with a "smart" device.
>
> > (2) The Bluetooth module is not capable of being a USB
> master,
>
> > (3) The code doesn't fit on chip - USB is "normally" for PC
> apps
> > where you have ample resources on the host.
>
> These are really part of the same issue. USB has a master/slave
> concept. The logic/code to be a slave is relatively small compared
> to that required to be a master.
>
> > As there are already a lot of USB-to-Bluetooth
> adapters/dongles
> > available in the market, I was just wondering how these
> devices
> > use USB for their applications. Can anybody shed some light
> > on this?
>
> They are devices and can be used, as you mentioned, for firmware
> upload, the connecting bus to the PC, ...
>
> But in general, they are devices (slaves) not hosts (masters).
>
> Marc Reinig
> System Solutions
>
>
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