getting rid of serial-getty@ttyAMA0.service

experiment/production/Misc-Notes.md

@@ -176,11 +176,12 @@ I followed [this](https://raspberrypi.stackexchange.com/questions/39165/how-can-
 systemctl stop serial-getty@ttyAMA0.service
 ```
 
-Disable permanently:
+Disable permanently (SO answer suggested the ['mask'](https://raspberrypi.stackexchange.com/questions/47671/why-my-program-wont-communicate-through-ttyama0-on-raspbian-jessie)):
 
 
 ```
 systemctl disable serial-getty@ttyAMA0.service
+systemctl mask serial-getty@ttyAMA0.service
 ```