Why is the BLE device not starting on my Arduino Pro Mini?
This is my wiring: First I connect the pro mini to the uno in order to upload the code looking like this:


Arduino Mini Pro to Arduino Uno

RX --&gt; TX
TX --&gt; RX
VCC --&gt; 5v
GND --&gt; GND
RST --&gt; RST


How would this work? The bootloader in the Uno and Mini Pro will both try to reply. You need a FTDI or a USB-to-UART module instead of the Uno. Alternatively, start by programming the Uno to act as a USB-to-UART converter using Serial and SoftwareSerial. 

Cheers!