From e5278b98fe2aad840d58e33a0c06af2e2b55cbde Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Fri, 7 Apr 2017 10:52:50 +0300
Subject: [PATCH] docs/esp8266/general: Start explicit "Known Issues",
 mentioned RTC inaccuracy.

---
 docs/esp8266/general.rst | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/docs/esp8266/general.rst b/docs/esp8266/general.rst
index cd659f80a..47df80d7b 100644
--- a/docs/esp8266/general.rst
+++ b/docs/esp8266/general.rst
@@ -107,8 +107,16 @@ This will allow to keep the structure of your application clear, as well as
 allow to install multiple applications on a board, and switch among them.
 
 
+Known Issues
+------------
+
 Real-time clock
----------------
+~~~~~~~~~~~~~~~
+
+RTC in ESP8266 has very bad accuracy, drift may be seconds per minute. As
+a workaround, to measure short enough intervals you can use
+``utime.time()``, etc. functions, and for wall clock time, synchronize from
+the net using included ``ntpdate.py`` module.
 
 Due to limitations of the ESP8266 chip the internal real-time clock (RTC)
 will overflow every 7:45h.  If a long-term working RTC time is required then
-- 
GitLab