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+ATmega Engine Controller
+========================
+
+The code from firmware/ is supposed to run on a ATmega48
+sending servo signals to cheap brushless controllers as used
+in RC models. The ATmega48 gets its instructions via a serial
+line from a host system. The code in client/ is a small test
+binary for the host system.
+
+Connection
+----------------
+
+	[Engine 1]--->[BLC 1]--->PB1
+	[Engine 2]--->[BLC 2]--->PB2
+	[Engine 3]--->[BLC 3]--->PB3
+	[Engine 4]--->[BLC 4]--->PD3
+	[Engine 5]--->[BLC 5]--->PD5
+	[Engine 6]--->[BLC 6]--->PD6
+
+	[Host TX]--->PD0
+	[Host RX]--->PD1
+
+Serial Protocol
+---------------
+
+Each of the following commands will be acknowledged with
+```0x2E```, which is the ASCII value for a dot. Available
+commands are:
+
+- **no operation**
+
+	This command simply does nothing. It consists of a
+	single byte: ```0x00```
+
+- **enable**
+
+	Sending the bytes ```0xCA```, ```0xFE```, ```0xBA```, ```0xBE``` activates
+	the engine controlling. Before sending this command
+	the controller does not activate any engine.
+
+- **disable**
+
+	One can disable all engines again by sending the
+	bytes ```0xDE```, ```0xAD```, ```0xBA```, ```0xBE```. After disabling the
+	engines with this command all future engine settings
+	will be ignored.
+
+- **set speed (of a single engine)**
+
+	To set the speed of a single engine on has to send
+	two bytes: first the engine number in the system
+	(```0x01``` - ```0x06```), the the desired speed (```0x00```-```0xFF```).
+
+- **set speed of all engines simultaneously**
+
+	One can also set the speed of all engines simultaneously
+	to the same value by first sending ```0xFF``` and then sending
+	a second byte with the desired speed (```0x00```-```0xFF```).