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README.md

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+# Cynthion: hardware design for a USB test instrument
+
+Cynthion is an open source hardware tool for building, testing, monitoring, and experimenting with USB devices. It is the primary platform for the [LUNA](https://github.com/greatscottgadgets/luna) USB gateware library based on [Amaranth HDL](https://github.com/amaranth-lang/amaranth).
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+Cynthion is designed in [KiCad](https://www.kicad.org/), an open source electronic design automation package.
+
+## Related Projects
+
+* [Cynthion](https://github.com/greatscottgadgets/cynthion): software for Cynthion
+* [LUNA](https://github.com/greatscottgadgets/luna): USB gateware library
+* [Apollo](https://github.com/greatscottgadgets/apollo): the firmware that runs on Cynthion's debug controller and which is responsible for configuring its FPGA
+* [Saturn-V](https://github.com/greatscottgadgets/saturn-v): a DFU bootloader created for Cynthion
+* [Packetry](https://github.com/greatscottgadgets/packetry): software for USB analysis
+* [Facedancer](https://github.com/greatscottgadgets/facedancer): software to create USB devices in Python