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README.md

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+usbscale
+========
+
+**Usbscale** is a program that reads weight data from a USB scale. Compilation
+is very simple and should work on any system with libusb-1.0 and gcc.
+
+Installation
+------------
+
+You will need the development headers for **libusb-1.0**. Once you have that, you simply need to run `make` in the source directory.
+
+Usage
+-----
+
+Simply run `usbscale` and it will automatically report on the first USB scale
+that it finds.  The weight will be output to `stdout`, while any diagnostic or
+error messages will be sent to `stderr`. An exit code of 0 means that a scale
+was found and a weight was successfully read. Any other error code indicates
+that a weight reading was unavailable.
+
+Adding support for more scales
+------------------------------
+
+By default, **usbscale** only supports a very limited number of USB scales. It
+does not search for just any USB scale, but only those listed in **scales.h**.
+To add support for another USB scale, it should be enough to add its vendor and
+product IDs to **scales.h**. In any case, you should contact me (see below) so
+that I can add your new scale to the main source code to benefit all users who
+may have the same scale.
+
+License
+-------
+
+The license for **usbscale** is the GPLv3, whose full text can be found in the
+file `COPYING`.  This means that you can reproduce and redistribute this
+software, as long as you provide any and all modifications that you have made
+to the software available under the same license. Notably, you may not
+integrate this software into another product without making the whole product
+open source. This paragraph is not definitive; please read the license
+carefully.
+
+Additional licensing terms may be negotiable.
+
+Contact
+-------
+
+The best way to contact me is by sending mail to erjiang at indiana.edu.