Datasheet

Bottom Side

On the back we also have SWDIO/SWCLK/RESET pins, these are used for programming the Bluefruit LE module itself.

SWD Debug Input

You normally should not connect to the SWDIO and SWCLK pins unless you want to wipe out the Bluefruit LE module

firmware for some reason, such as flashing an entirely custom firmware image written by yourself, though this is

entirely at your own risk since it will wipe the Bluefruit firmware! Flashing firmware or using the SWD interface will

require something like a Segger J-Link EDU Mini (https://adafru.it/yDp) to communicate via the debug controller inside

the nRF51822.

Factory Reset

The Reset pad (not to be confused with the 0.1" circular RST pin!) is the factory reset pin, which is also rarely used, but

you can use it to set the module back to the factory default settings if it gets really messed up. Connect the 'Reset' pin

to GND when you boot the device up to force a factory reset in HW (via the bootloader).