diff --git a/Device-Tests-&-Coverage-Report.md b/Device-Tests-&-Coverage-Report.md
index b1076dc..9f98fe0 100644
--- a/Device-Tests-&-Coverage-Report.md
+++ b/Device-Tests-&-Coverage-Report.md
@@ -15,7 +15,7 @@ You need python + [pyserial 3.4](https://pythonhosted.org/pyserial/) which inclu
 
 On Linux the ``rfc2217_server.py`` is typically available in ``usr/share/doc/python-serial/examples``. On Windows you have to take it from github.
 
-On a Raspi 3 you have to [configure](https://www.raspberrypi.org/documentation/configuration/uart.md) the PL011-UART instead of the mini-UART for the GPIO pins.
+On a Raspi 3 you have to [configure](https://www.raspberrypi.org/documentation/configuration/uart.md) the PL011-UART instead of the mini-UART for the GPIO pins, by using _disable-bt_ or _miniuart-bt_ overlay.
 
 Before executing the test, start the *rfc2217* server with: ``python rfc2217_server.py -v`` *com-port*