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README.md

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+# fxSDK
+
+The fxSDK is a development kit for Casio graphing calculators of the family of
+the fx-9860G and fx-CG 50. It's a set of command-line compilation and project
+tools used to facilitate development with the
+[gint library](/Lephenixnoir/gint).
+
+This kit is free software; you may use it for any purpose, share it, and modify
+it as long as you share your changes. No credit required, but please let me
+know!
+
+The fxSDK is compatible with Linux and has been successfully built on Mac OS.
+If there are compatibility issues, I am willing to try and port stuff to your
+favorite operating system.
+
+## Tool description
+
+### Project management (_fxsdk_)
+
+`fxsdk` lets you set up projects almost instantly with a default folder
+structure and a working Makefile linking against gint for both fx-9860G and
+fx-CG 50. You can then use it to build and transfer your add-ins to a
+calculator.
+
+Most project parameters can be changed just by editing a text file annotated
+with the role and description of each option.
+
+`fxsdk` only writes files at project creation time, so you keep control over
+your build system and configuration - it just helps you get started faster.
+
+### G1A file generation (_fxg1a_)
+
+`fxg1a` is a versatile g1a file editor that creates, edits and dumps the header
+of fx-9860G add-ins files. It is used to build a g1a file out of a binary
+program.
+
+It supports PNG icons, checking the validity and checksums of the header,
+repairing broken headers and dumping both the application data and icon.
+
+### Data conversion (_fxconv_)
+
+`fxconv` is a tool that interacts specifically with gint. It converts data
+files such as images and fonts into gint-specific format and embeds the result
+into object files that expose a single variable.
+
+### OS disassembly and study (_fxos_)
+
+`fxos` is a powerful disassembler and OS fiddling tool. It knows the structure
+of OS files and can extract metadata, language information and syscalls through
+a simple command-line interface.
+
+Its key feature is the production of annotated assembler listings where
+syscalls invocations and peripheral registers are identified and named. This
+makes it a lot easier to climb back abstraction levels from the code.
+
+## Build instructions
+
+The fxSDK is platform-agnostic; a single install will cover any target
+platforms. There's only one noticeable dependency:
+
+* libpng ≥ 1.6
+
+First configure; you can specify the install folder with `--prefix`, which
+defaults to your local home folder. You can also enable or disable tools.
+Broadly, you will need:
+
+* `fxsdk` if you want to benefit from the automated project setup
+* `fxg1a` if you want to compile add-ins for fx-9860G
+* `fxconv` if you want to compile gint or develop add-ins with it
+* `fxos` if you want to disassemble or study OS dumps
+
+Each tool can be enabled or disabled with `--enable-<tool>` and
+`--disable-<tool>`. For a default build you need no arguments:
+
+```sh
+% ./configure
+```
+
+Then make and install as usual.
+
+```sh
+% make
+% make install
+```
+
+If you selected an install folder for which you don't have write access (which
+apparently includes the default folder on Mac OS), you will need `sudo` to
+install.
+
+## Usage instructions
+
+Most details are covered in the help of each individual tool, which you can get
+with `-h`, `--help` or by invoking each tool without arguments.