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Hello USB experts,
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.
(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.
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?
Thanks,
Ricky Nite
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