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README.md

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+# Siena - Super Nintendo (SNES) emulator
+
+[![Build and test](https://github.com/twvd/siena/actions/workflows/build_test.yml/badge.svg)](https://github.com/twvd/siena/actions/workflows/build_test.yml) [![codecov](https://codecov.io/github/twvd/siena/graph/badge.svg?token=12207MF9CW)](https://codecov.io/github/twvd/siena)
+
+Siena is a Super Nintendo / Super Famicom emulator, written in Rust. This emulator is a hobby project born out of nostalgia. It is currently a work in progress and not really fit for playing games.
+
+Current features and state:
+ * SDL2 graphical frontend
+ * Supports LoROM / HiROM cartridges, with auto-detect
+ * Fully functional (native-mode only), cycle accurate 65816 main CPU core
+ * Fully functional, cycle accurate SPC700 audio CPU core
+ * Functional DMA and HDMA
+ * PPU modes 0, 1, 3 functional
+ * Color math
+
+## Building and running
+
+After checking out the source, run the following command to build and run the emulator, specifying a ROM:
+
+```sh
+cargo run --release -- path/to/rom.smc
+```
+
+## Tests
+
+This project is tested against:
+ * Self-written unit tests
+ * [https://github.com/TomHarte/ProcessorTests/tree/main/65816](Synthetic 65816 CPU tests)
+ * [https://github.com/raddad772/jsmoo/tree/main/misc/tests/GeneratedTests/spc700/v1](Synthetic SPC700 CPU tests)
+ * A collection of test ROMs by various people
+
+Test input lives in a [separate repository](https://github.com/twvd/siena_tests) as they are rather large.
+
+To run tests:
+
+1. Checkout [siena_tests](https://github.com/twvd/siena_tests]) at the same level as this repository (so you have 'siena' and 'siena_tests' at the same directory level).
+2. In the directory of this repository, run `cargo test`.
+
+Coverage data is available on [Codecov](https://app.codecov.io/gh/twvd/siena).
+
+![codecov sunburst](https://codecov.io/github/twvd/siena/graphs/sunburst.svg?token=12207MF9CW)