# Onefinity sample code - why M7? **URL:** \ **Category:** Original/PRO Series (Buildbotics) (Gen 1)\ **Created:** [August 9, 2024, 2:41am UTC](https://forum.onefinitycnc.com/t/onefinity-sample-code-why-m7/28179 "2024-08-09T02:41:48Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![aero23](https://avatars.discourse-cdn.com/v4/letter/a/76d3ee/32.png) [@aero23](https://forum.onefinitycnc.com/u/aero23)\ **Post date:** [August 9, 2024, 2:41am UTC](https://forum.onefinitycnc.com/t/onefinity-sample-code-why-m7/28179/1 "2024-08-09T02:41:48Z")
I’m looking through the sample code that comes loaded on the BB controller and I’m wondering why M7 is in there? ---
**Author:** ![349iq2345](https://avatars.discourse-cdn.com/v4/letter/3/bb73d2/32.png) [@349iq2345](https://forum.onefinitycnc.com/u/349iq2345)\ **Post date:** [August 9, 2024, 3:01am UTC](https://forum.onefinitycnc.com/t/onefinity-sample-code-why-m7/28179/2 "2024-08-09T03:01:32Z")
Hey Chris, - [M7 (turn workpiece mist coolant on)](https://linuxcnc.org/docs/html/gcode/m-code.html#mcode:m7-m8-m9) usually this is for turning on [workpiece coolant](https://en.wikipedia.org/wiki/Cutting_fluid). It activates ‘Load-1’ output (pin 2) on [25-pin I/O port](https://buildbotics.com/manual-v1-0/#25pinioport). But it may be used for other purposes, depending on what you connect to ‘Load-1’ output. ---
**Author:** ![aero23](https://avatars.discourse-cdn.com/v4/letter/a/76d3ee/32.png) [@aero23](https://forum.onefinitycnc.com/u/aero23)\ **Post date:** [August 9, 2024, 3:09pm UTC](https://forum.onefinitycnc.com/t/onefinity-sample-code-why-m7/28179/3 "2024-08-09T15:09:21Z")
Thanks. Yeah, I know it’s a coolant command, that’s why I was curious. And I realize that it’s just a voltage at a pin so one could put whatever they want there, but I was wondering why it was in this example code for the test piece? Is it intended to turn a vacuum on maybe?