added README.

README.md

@@ -0,0 +1,45 @@
+
+h1. Aquamaniac Home Control System (AqHCS)
+
+h2.Overview
+
+Home automation/control system consists of multiple parts:
+- nodes
+  - small PCBs based on AVR microcontrollers
+    - AtTiny84
+    - AtTiny85
+    - AtTiny841
+    - AtMega644
+  - modular operating system written in AVR assembler
+  - driver modules for busses:
+    - one-wire bus
+    - two-wire-bus
+    - SPI bus
+  - driver modules for devices/sensors modules:
+    - UART
+    - DS18b20  sensors for temperature measurement
+    - SI7021   sensors for temperature and humidity measurement
+    - SGP_30   sensors for air quality measurement
+    - ccs811   sensors for air quality measurement
+    - I2C displays (work-in-progress)
+    - SPI displays (work-in-progress)
+  - inter-node communication stack using two wires (clock/data)
+
+- applications
+  - aqhome-data
+    - TCP data service receiving sensor data
+  - aqhome-nodes
+    - service receiving sensor data via inter-node bus from nodes
+      and forwarding that data to aqhome-data
+  - aqhome-mqttlog
+    - service exchanging data between aqhome-data service and a
+      mqtt server
+  - aqhome-react
+    - service reacting to data received by aqhome-data (home automation service)
+  - aqhome-tool
+    - tool to manipulate aqhome-data (e.g. edit devices and values,
+      adding data points, create graphs from aqhome-data)
+    - tool to flash firmware for nodes, list nodes
+  - aqhome-cgi
+    - HTTP service for user interaction with aqgome-data
+