SatCat5 by ooterness
SatCat5 is FPGA software that implements a low-power, mixed-media Ethernet switch. It is functionally equivalent to commercially available, unmanaged Ethernet switches for home use, except that it also supports lower-speed connections to the same network using SPI or UART. These lower-rate data links, (commonly used in simple, low-cost, low-power microcontrollers) allow nearly any device to participate in the same local communication network, regardless of its capability level.
Like any Ethernet switch, this one has multiple ports; each port is a point-to-point link from the switch to a network device, which could be a PC, a microcontroller, or even another switch. Power draw required for the switch itself is well under 1 watt.
A major goal of the SatCat5 project is to support a variety of endpoints, from simple microcontrollers to a full-fledged PC, all connected to the same Ethernet network.
A complete listing of supported interfaces is available here. The list includes the usual 10/100/1000 Mbps "Media Independent Interfaces" (RMII, RGMII, SGMII) as well as media and physical-layer options that aren't usually used with Ethernet (SPI, UART). The latter options are typically lower speed (1-10 Mbps), but use physical layer protocols that are more amenable to use with simple microcontrollers. All interfaces transmit and receive standard Ethernet Frames.
Detailed version history is available in the changelog.
More information is available in the Frequently Asked Questions.
What Is Provided
This project is effectively a set of building blocks, ready to be used to build your own custom Ethernet switch. The switch can be optimized to your needs, tailored to your preferred platform, port count, interface types, etc.
However, we do include several reference designs that showcase many of the available features. The easiest way to get started is with the Digilent Arty A7, a low-cost FPGA development board. We've included a reference design that specifically targets this board. PMOD connector pinouts are chosen to be directly compatible with off-the-shelf USB-UART adapters.
Other reference designs include the prototype that we built to develop, test, and demonstrate the SatCat5 switch. It is intended to run on many off-the-shelf FPGA development boards, using an FMC port to attached to a custom PCB. The custom PCB includes Ethernet transceivers, PMOD connectors, and other I/O.
The main expected users of this project are cubesat and smallsat developers. By encouraging everyone to use this technology, we create a mutually-compatible ecosystem that will make it easier to develop new small-satellite payloads, and simultaneously make it easier to integrate those payloads into vehicles.
However, we think the same technology might be useful to other embedded systems, including Internet-of-Things systems that want to integrate microcontrollers onto a full-featured LAN.
If you'd like to build the Arty example design, you'll need the Vivado Design Suite. We've tested with version 2015.4, 2016.3, and 2019.1, but it should work as-is with most other versions as well. Once it's installed, simply run "make arty_35t" in the root folder. (Or follow the equivalent steps under Windows.)
If you'd like to build your own design, create a new top-level VHDL file and add the following:
- Any number of port_xx blocks. (e.g., port_spi, port_uart, port_rgmii, etc.)
- At least one switch_core block.
- One is always functionally adequate.
- Sometimes you can save memory, power, and other resources if you use two.
- One switch_aux block. This provides error-reporting, status LEDs, and other niceties.
- Clock generation. Check the documentation for selected port type(s) to see what's needed.
More information is available in the Frequently Asked Questions.
- doc: Documentation and associated images.
- project: Project files for building the design or running simulations
- icecube2_2017.8: Project files for building example designs in Lattice iCEcube2. (Tested with version 2017.8.)
- libero_12.3: Project files for building example designs in Microsemi Libero. (Tested with version 12.3.)
- modelsim_10.0a: Project files for running VHDL simulations in ModelSim. (Tested with version 10.0a.)
- vivado_2015.4: Project files for building or simulating the design on Xilinx FPGAs. (Tested with Vivado version 2015.4.)
- sim: Simulation and verification of the VHDL design.
- matlab: MATLAB/Octave scripts used to generate certain lookup tables.
- test: Test data for various unit-test simulations.
- vhdl: VHDL unit tests for individual functional blocks.
- src: Source code for the core SatCat5 design
- vhdl/common: VHDL implementation of most functional blocks. (Common / all platforms)
- vhdl/lattice: Platform-specific VHDL for the Lattice iCE40.
- vhdl/microsemi: Platform-specific VHDL for the Microsemi Polarfire.
- vhdl/xilinx: Platform-specific VHDL for Xilinx Artix7 and Kintex7. (Including Arty and AC701 example designs.)
- test: Additional testing, including the prototype reference design.
- chat_client: A demo application that implements chatroom functions using raw Ethernet frames.
- pi_wire: A tool for connecting to SatCat5 with a Raspberry Pi.
- proto_pcb: PCB design files for the prototype reference design.
We encourage you to contribute to SatCat5! Please check out the guidelines here for information on how to submit bug reports and code changes.
Portions of SatCat5 are patent pending, USPTO application number 16/708,306.
In accordance with SatCat5's LGPL license agreement, we grant a royalty-free license for use of this technology. Refer to section 11 of the GPLv3 license for details.
Copyright 2019, 2020 The Aerospace Corporation
This file is part of SatCat5.
SatCat5 is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
SatCat5 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with SatCat5. If not, see https://www.gnu.org/licenses/.
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If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee. END OF TERMS AND CONDITIONS How to Apply These Terms to Your New Programs If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. <one line to give the program's name and a brief idea of what it does.> Copyright (C) <year> <name of author> This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>. Also add information on how to contact you by electronic and paper mail. If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode: <program> Copyright (C) <year> <name of author> This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an "about box". You should also get your employer (if you work as a programmer) or school, if any, to sign a "copyright disclaimer" for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see <https://www.gnu.org/licenses/>. The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read <https://www.gnu.org/licenses/why-not-lgpl.html>.