We have a custom embedded device that uses Roving Networks' RN240 bluetooth adapter on an RS232 port to communicate with another device via bluetooth. It is working well, but I am attempting to "bulletproof" the management of the bluetooth connection as there is an occasional hiccup and I need to handle these circumstances.
In the flow I'm working on, I put the adapter into Command mode and get back the proper response:
> CMD
< $$$
I am then able to issue commands to it to Get or Set information. One of the things we do is specify which bluetooth device to pair to using these commands. The device may already have a valid pairing, and is set to Auto Master mode. When the device powers up, it may automatically connect to our other bluetooth device (as designed). I need to know if the dongle has paired when I am attempting to perform certain functions.
The command set specification specifically says that when the Get command
> GK
< 1
is sent to the device (to obtain current connection status), it will respond with a "0" for "Not Connected" or "1" for "Connected"
I am occasionally getting a "4" when the device is either connecting or connected, and I've been unable to isolate why. Once I start getting a "4", I keep getting a "4" every time I inquire after that. I have to power down the dongle (ie: reset my test scenario) to get a different behavior.
I've poked through other Advanced User Guides on Roving Networks' website, and googled as many variations as I can think of to find what this status means. It seems when I get back "4", I can no longer control the Bluetooth Adapter as I need to. I would like to know what "4" means, and what I can do to recover the device so I can make it do what I want to!
Thanks! I appreciate any help.
(For reference, here's the page for this adapter, along with links for downloading the command set: Roving Networks RN240 Bluetooth Adapter)
EDIT: I have heard back from Microchip Engineering Support. Their answer was that "4" is an undocumented state, as it shouldn't be visible to the user. "4" means the chip in in a connecting state, and that if the module is getting into this state, it is recommended that the module be rebooted (with the "R,1" command).
