how to send data to Adafruit Bluefruit Feather (32u4) over bluetooth? Sup yo.

I have my Adafruit Bluefruit Feather all wired up.  It's lovely.  I've got it responding to commands over the USB serial, activating an array of octocouplers.  It's terrific.  Here's the thing though.  I need to talk to it wirelessly.

I can only pair it (MacOS) the Adafruit Bluefruit LE Connect app.  It doesn't show up in my Bluetooth preference pane.

$ ls /dev/tty.*  shows /dev/tty.Bluetooth-Incoming-Port and the Arduino IDE can see it.  Unfortunately the word Incoming is right there in the middle of that port name.  Sending commands through the Arduino serial monitor doesn't seem to do anything.

The Bluefruit connect app appears to be able to send commands over something called UART but my board doesn't respond to the stuff that works over USB serial.

How do I talk to this board over Bluetooth?
The “UART” being referred to is the Nordic UART GATT Service. This is not a serial port or USB connection. It is a high level BLE protocol that simulates a serial port via the Bluetooth connection. 

In order to connect to the device from your Mac you’ll need to write some C or Obj-C. I’ve done this for Windows, but not a Mac, so I’m afraid I can’t give you detailed instructions. However, the source code for the iOS Adafruit Bluefruit LE Connect app you’re using is open source and should be a good starting point. 

Be warned of a few things though. 


You’re going to have to learn a bit about the BLE protocols and standards. It’s not exactly for the faint of heart. 
Apple throttles the speed/throughput of BLE for their iOS devices (as does Android) to protect battery life. I don’t know if they apply the same throttling to their laptops. You may not be able to achieve a satisfying data rate if you’re looking to create a high throughput “data pipe”.  With Win10 and the Bluefruit LE I was able to achieve 40 bytes every 30ms. You’ll likely be limited to 20 every ~30ms. 

If you’re looking to just send some occasional text (maybe AT style) commands to the device via BLE though, you won’t come close to those limitations.