From 32ab928aa83bcaaa9b72651ce7dc80c359e519cf Mon Sep 17 00:00:00 2001
From: Laurens Valk <laurens@pybricks.com>
Date: Tue, 7 Apr 2020 13:40:37 +0200
Subject: [PATCH] doc/ev3devices/UltrasonicSensor: add freeze note

Simplify the text for silent mode, and add a note to say what to do if it stops working when the UART gets confused.
---
 pybricks/ev3devices.py | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/pybricks/ev3devices.py b/pybricks/ev3devices.py
index 5b83a36..8086fec 100644
--- a/pybricks/ev3devices.py
+++ b/pybricks/ev3devices.py
@@ -222,13 +222,10 @@ class UltrasonicSensor:
 
         Arguments:
             silent (bool): Choose ``True`` to turn the sensor off after
-                           measuring the distance. Choose ``False`` to leave
-                           the sensor on. When you choose
-                           ``silent=True``, the sensor does not
-                           emit sounds waves except when taking the
-                           measurement. This reduces interference with other
-                           ultrasonic sensors, but turning the sensor off takes
-                           approximately 300 ms each time.
+                           measuring the distance. This reduces interference
+                           with other ultrasonic sensors. If you do
+                           this too frequently, the sensor can freeze.
+                           If this happens, unplug it and plug it back in.
 
         Returns:
             :ref:`distance`: Distance.