title: Communicating over bluetooth SPP using USB dongle without implementing the Host Stack
body: <p>I've been asked to find a way to implement bluetooth communication to an android powered smartphone in our custom embedded application. We are using the FTDI Vinculum II (VNC2) for the USB host controller, and my boss would like a solution where the customer can plug in any (or most) bluetooth USB dongles into the USB port on our instrument and then be able to connect our instrument via bluetooth to an android phone.</p>
  
  <p>I've found out the USB dongle only implements the Controller Stack (HCL/SCO, LMP, and HCI) and that the Host (my custom firmware in this case) must provide the implementation of the Host Stack, or the parts of it that we need in any case (HCI, L2CAP, RFCOMM at least).</p>
  
  <p>My question is, is there any way around having to implement the host stack from scratch? Are there any reasonably priced dongles that are "host-less" (eg. they implement both the host and controller portions of the bluetooth stack and communicate with a simple protocol) that we could just provide along with our instrument? I know of the RovingNetworks FirePlug which does this and we have one and have gotten it to work but it is $70 and very large. I am looking for a similar solution that is not so costly and also smaller profile so that it doesn't stick so far out of our handheld instrument... either that or another solution that I am not aware of that would allow our customers to plug any USB bluetooth dongle into our instrument and be able to connect to their android phone without us having to implement the bluetooth host stack on our end...</p>
  
  <p>Thanks in advance for any information.</p>