docs: convert to .rst and add readthedocs

Author: igrr

.travis.yml

@@ -3,23 +3,25 @@ language: bash
 os:
   - linux
 
-addons:
-  apt:
-    sources:
-      - ubuntu-toolchain-r-test
-    packages:
-      - g++-4.8
+dist: trusty
+
+install:
+  - pip install --user -r doc/requirements.txt
 
 script:
   - set -e
-  - export CXX="g++-4.8" CC="gcc-4.8" GCOV="gcov-4.8"
+  - echo -e "travis_fold:start:docs"
+  - pushd $TRAVIS_BUILD_DIR/doc
+  - SPHINXOPTS="-W" make html
+  - popd
+  - echo -e "travis_fold:end:docs"
   - echo -e "travis_fold:start:host_tests"
   - pushd $TRAVIS_BUILD_DIR/tests/host
   - make
   - make clean-objects
+  - popd
   - echo -e "travis_fold:end:host_tests"
   - echo -e "travis_fold:start:sketch_test_env_prepare"
-  - popd
   - wget -O arduino.tar.xz https://www.arduino.cc/download.php?f=/arduino-nightly-linux64.tar.xz
   - tar xf arduino.tar.xz
   - mv arduino-nightly $HOME/arduino_ide
@@ -42,10 +44,6 @@ script:
   - cat size.log
   - echo -e "travis_fold:end:size_report"
 
-after_success:
-    - pushd $TRAVIS_BUILD_DIR/tests/host
-    - bash <(curl -s https://codecov.io/bash) -X gcov
-
 notifications:
   email:
     on_success: change

doc/.gitignore

@@ -0,0 +1 @@
+_build

doc/Makefile

@@ -0,0 +1,20 @@
+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line.
+SPHINXOPTS    =
+SPHINXBUILD   = sphinx-build
+SPHINXPROJ    = ESP8266ArduinoCore
+SOURCEDIR     = .
+BUILDDIR      = _build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

doc/Troubleshooting/debugging.md

@@ -0,0 +1,107 @@
+Debugging
+=========
+
+Introduction
+------------
+
+Since 2.1.0-rc1 the core includes a Debugging feature that is
+controllable over the IDE menu.
+
+The new menu points manage the real-time Debug messages.
+
+Requirements
+~~~~~~~~~~~~
+
+For usage of the debugging a Serial connection is required (Serial or
+Serial1).
+
+The Serial Interface need to be initialized in the ``setup()``.
+
+Set the Serial baud rate as high as possible for your Hardware setup.
+
+Minimum sketch to use debugging:
+
+.. code:: cpp
+
+    void setup() {
+        Serial.begin(115200);
+    }
+
+    void loop() {
+    }
+
+Usage
+~~~~~
+
+1. Select the Serial interface for the Debugging messages: |Debug-Port|
+
+2. Select which type / level you want debug messages for: |Debug-Level|
+
+3. Check if the Serial interface is initialized in ``setup()`` (see
+   `Requirements <#requirements>`__)
+
+4. Flash sketch
+
+5. Check the Serial Output
+
+Informations
+------------
+
+It work with every sketch that enables the Serial interface that is
+selected as debug port.
+
+The Serial interface can still be used normal in the Sketch.
+
+The debug output is additional and will not disable any interface from
+usage in the sketch.
+
+For Developers
+~~~~~~~~~~~~~~
+
+For the debug handling uses defines.
+
+The defined are set by command line.
+
+Debug Port
+^^^^^^^^^^
+
+The port has the define ``DEBUG_ESP_PORT`` possible value: - Disabled:
+define not existing - Serial: Serial - Serial1: Serial1
+
+Debug Level
+^^^^^^^^^^^
+
+All defines for the different levels starts with ``DEBUG_ESP_``
+
+a full list can be found here in the
+`boards.txt <https://github.com/esp8266/Arduino/blob/master/boards.txt#L180>`__
+
+Example for own debug messages
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The debug messages will be only shown when the Debug Port in the IDE
+menu is set.
+
+.. code:: cpp
+
+    #ifdef DEBUG_ESP_PORT
+    #define DEBUG_MSG(...) DEBUG_ESP_PORT.printf( __VA_ARGS__ )
+    #else
+    #define DEBUG_MSG(...) 
+    #endif
+
+    void setup() {
+        Serial.begin(115200);
+        
+        delay(3000);
+        DEBUG_MSG("bootup...\n");
+    }
+
+    void loop() {
+        DEBUG_MSG("loop %d\n", millis());
+        delay(1000);
+    }
+
+.. |Debug-Port| image:: debug_port.png
+.. |Debug-Level| image:: debug_level.png
+