> For the complete documentation index, see [llms.txt](https://nxp.gitbook.io/rddrone-bms772/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://nxp.gitbook.io/rddrone-bms772/board-user-guide/getting-started-with-the-rddrone-bms772/how-to-use-the-sw-emergency-button-kill-switch-cut-off.md).

# How to use the SW emergency button / kill switch / cut off

Add the emergency button / kill switch (Normally Closed, NC) to J21 pin 6 and pin 8 (GND) like in the picture below.

In the SW, please configure it to be an emergency button with: “bms set emergency-button-enable 1”.

This will enable the pull-up resistor on MCU pin PTE8. When the emergency button is pressed, the connection to ground is broken and the pin will be high. This will generate a SW emergency stop and the BMS state machine will go to the FAULT state.

<figure><img src="/files/Wwopa7x6Pln1NFguAuTO" alt=""><figcaption></figcaption></figure>