"Q12. I am trying to connect my Bluno Beetle (acting as Central) with other BLE Arduino device, which is Adafruit Bluefruit (nRF51822). I have already everything I should. The Bluefruit BLE is default set to peripheral mode (as its firmware only supports peripheral mode actually). Any ideas why the connection doesn't want to establish automatically?
A. This is a compatibility problem. DFRobot BLE series products are all compatible, while not with other brand. This is why even with a pc(Linux, Windows, Mac etc.) which has the BLE feature, you still need to use a USB BLE-Link to work with our BLE product."
I've been using their BLE dongle they mention and it's working for me with the Bluno Beetle. I believe they both use the TI CC2540 BLE chip, whereas the dongle you're using has a Qualcomm chip. Not sure if that is what's causing your problem.
You Reply:Excuse my ignorance, but is the pairing pin number the same as the 6 digit Bluetooth passcode? I think the Beetle BLE firmware leverages the TI BLE stack software, based on this comment in the GIT repo:
https://github.com/DFRobot/BLE_firmware_V1.9
Recompile BLE firmware with official protocol stack:BLE-CC254x-1.4.0
I downloaded the TI development SW from their web site, and saw these two default passcodes in some of the BLE C-based applications they have prepared for customers of their devices: