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+## General Usage
+
+### Prerequisites
+
+You must have avr-gcc and avrdude installed. To install both
+tools on a debian-based system, please run the following
+command:
+
+    apt install avr-gcc avrdude
+
+The names for these dependencies may differ for other package
+managers and distributions. Please check the package sources
+on your system for more information.
+
+### Build and Flash
+
+Run this next command in the project root directory to
+build and flash the project using an USBasp programmer:
+
+    make all
+
+See the Makefile for different settings for your specific
+build environment. To remove all build related auxiliary
+files you may run these commands:
+
+    make clean
+    make distclean
+
+You can listen on the serial debug interface using the
+command below (if you have initialized the optional
+submodules as described in the next section):
+
+    make listen
+
+### Temperature and Dewpoint Targets
+
+You can use the script below to send serial commands (you
+may need to run `git submodule update --init` if the tools
+directory is empty):
+
+    ./opt/tools/serial-send.py <command> <args, ...>
+
+Issue the SET command to update the target settings:
+
+    set <temperature> <dewpoint>
+
+Settings are stored in EEPROM and are persistent until a new
+SET command is issued. Keywords are not case-sensitive. Both
+arguments may contain a decimal point followed by a sequence
+of digits.