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the-aerospace-corporation
satcat5
VHDL2023–2025
the-aerospace-corporation / satcat5

satcat5

SatCat5 is a mixed-media Ethernet switch that lets a variety of devices communicate on the same network.

Systems & InfrastructureCreative & MediaNetworking
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4Distinct people
6Mentions
0Explicit recommenders
514GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

SatCat5 is a mixed-media Ethernet switch that lets a variety of devices communicate on the same network.

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 5:04:57 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by month6 dated mentions

Observed mentions: 2023-02-16 11:52:25 UTC to 2025-09-15 23:38:03 UTC.

012342023-02-01 00:00:00 UTC to 2023-03-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsFeb 20232023-03-01 00:00:00 UTC to 2023-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-04-01 00:00:00 UTC to 2023-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-05-01 00:00:00 UTC to 2023-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-06-01 00:00:00 UTC to 2023-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-07-01 00:00:00 UTC to 2023-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-08-01 00:00:00 UTC to 2023-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-09-01 00:00:00 UTC to 2023-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-10-01 00:00:00 UTC to 2023-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-11-01 00:00:00 UTC to 2023-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-12-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-01-01 00:00:00 UTC to 2024-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-02-01 00:00:00 UTC to 2024-03-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-03-01 00:00:00 UTC to 2024-04-01 00:00:00 UTC (exclusive): 4 mentions; 1 submissions, 3 comments2024-04-01 00:00:00 UTC to 2024-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-05-01 00:00:00 UTC to 2024-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsMay 20242024-06-01 00:00:00 UTC to 2024-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-07-01 00:00:00 UTC to 2024-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-08-01 00:00:00 UTC to 2024-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-09-01 00:00:00 UTC to 2024-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-10-01 00:00:00 UTC to 2024-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-11-01 00:00:00 UTC to 2024-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-12-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-01-01 00:00:00 UTC to 2025-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-02-01 00:00:00 UTC to 2025-03-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-03-01 00:00:00 UTC to 2025-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-04-01 00:00:00 UTC to 2025-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-05-01 00:00:00 UTC to 2025-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-06-01 00:00:00 UTC to 2025-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-07-01 00:00:00 UTC to 2025-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-08-01 00:00:00 UTC to 2025-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-09-01 00:00:00 UTC to 2025-10-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsSep 2025

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Feb 20232023-02-01 00:00:00 UTC2023-03-01 00:00:00 UTC110
Mar 20232023-03-01 00:00:00 UTC2023-04-01 00:00:00 UTC000
Apr 20232023-04-01 00:00:00 UTC2023-05-01 00:00:00 UTC000
May 20232023-05-01 00:00:00 UTC2023-06-01 00:00:00 UTC000
Jun 20232023-06-01 00:00:00 UTC2023-07-01 00:00:00 UTC000
Jul 20232023-07-01 00:00:00 UTC2023-08-01 00:00:00 UTC000
Aug 20232023-08-01 00:00:00 UTC2023-09-01 00:00:00 UTC000
Sep 20232023-09-01 00:00:00 UTC2023-10-01 00:00:00 UTC000
Oct 20232023-10-01 00:00:00 UTC2023-11-01 00:00:00 UTC000
Nov 20232023-11-01 00:00:00 UTC2023-12-01 00:00:00 UTC000
Dec 20232023-12-01 00:00:00 UTC2024-01-01 00:00:00 UTC000
Jan 20242024-01-01 00:00:00 UTC2024-02-01 00:00:00 UTC000
Feb 20242024-02-01 00:00:00 UTC2024-03-01 00:00:00 UTC000
Mar 20242024-03-01 00:00:00 UTC2024-04-01 00:00:00 UTC413
Apr 20242024-04-01 00:00:00 UTC2024-05-01 00:00:00 UTC000
May 20242024-05-01 00:00:00 UTC2024-06-01 00:00:00 UTC000
Jun 20242024-06-01 00:00:00 UTC2024-07-01 00:00:00 UTC000
Jul 20242024-07-01 00:00:00 UTC2024-08-01 00:00:00 UTC000
Aug 20242024-08-01 00:00:00 UTC2024-09-01 00:00:00 UTC000
Sep 20242024-09-01 00:00:00 UTC2024-10-01 00:00:00 UTC000
Oct 20242024-10-01 00:00:00 UTC2024-11-01 00:00:00 UTC000
Nov 20242024-11-01 00:00:00 UTC2024-12-01 00:00:00 UTC000
Dec 20242024-12-01 00:00:00 UTC2025-01-01 00:00:00 UTC000
Jan 20252025-01-01 00:00:00 UTC2025-02-01 00:00:00 UTC000
Feb 20252025-02-01 00:00:00 UTC2025-03-01 00:00:00 UTC000
Mar 20252025-03-01 00:00:00 UTC2025-04-01 00:00:00 UTC000
Apr 20252025-04-01 00:00:00 UTC2025-05-01 00:00:00 UTC000
May 20252025-05-01 00:00:00 UTC2025-06-01 00:00:00 UTC000
Jun 20252025-06-01 00:00:00 UTC2025-07-01 00:00:00 UTC000
Jul 20252025-07-01 00:00:00 UTC2025-08-01 00:00:00 UTC000
Aug 20252025-08-01 00:00:00 UTC2025-09-01 00:00:00 UTC000
Sep 20252025-09-01 00:00:00 UTC2025-10-01 00:00:00 UTC101

What Hacker News says

6 sources
ooterness·Mar 31, 2024
I needed 128-bit and 256-bit integers on an embedded project recently. In short, it was for fixed-point digital signal processing. The raw input and output samples were int64_t. We needed to add, subtract, multiply, and accumulate these to do filtering and linear regression with no loss of precision. Conventional bigintegers weren't an option because the target application doesn't allow heap allocation. So we rolled our own [1] stack-allocated, fixed-width big integer class. [1] https://github.com/the-aerospace-corporation/satcat5/blob/ma...
In Layout of Rust's u128 and i128 changed
ooterness·Mar 17, 2024
Power consumption varies a lot with the number of ports and the FPGA platform. The "ac701_proto_v1" example design for the Xilinx Artix7-200T has 4 SPI/UART ports and 4 gigabit ports (a mix of RGMII and SGMII). That design hits around 150-700 mW [1], depending on how many gigabit ports are active. One way we've saved a lot of power is by skipping the Ethernet PHY. Last time I looked, a 100BASE-T PHY was about 130 mW each and a 1000BASE-T PHY was about 480 mW each. Double that because both ends of the link need a PHY, and that roughly lines up with your numbers. The upside of using a PHY is that "real Ethernet" can drive hundreds of meters of cable. The PHY chip is effectively a converter from the local interface (*MII) to the long-distance interface (10/100/1000BASE-T). But on a cubesat or a small UAV, cables are short, so you can s
Read the rest
kip that conversion to save power on both ends. The downside is that the many *MII flavors are not mutually compatible. Regarding the Gecko connectors, the very simple reason to avoid screws is floorspace. The "Handle" payload interface unit [2] has 12 Gecko connectors in a 4x3 grid. The screw mounts add enough width that it wouldn't fit in the allotted space. The retention clips are quite robust, though you do need a small tool to remove them. There's no reason you couldn't have screws on one end of the cable and clips on the other. Regarding the Tyco connectors, it's definitely a compromise that we might revisit. Size and signal integrity were the main concerns. The space industry is quite risk-averse, so something with provable signal integrity for 1250 Mbaud SGMII signals was a necessity. The GadgetSmyth product line is quite interesting. I had not heard of that company before. I'm surprised that their 1000BASE-T pigtails are not using twinax or STP cable, but the switch cards are definitely aligned with what we're trying to accomplish. [1] https://digitalcommons.usu.edu/smallsat/2020/all2020/174/ [2] https://github.com/the-aerospace-corporation/satcat5/blob/ma...
In Show HN: SatCat5, the open-source FPGA Ethernet switch
minetest2048·Mar 17, 2024
Hi! I'm one of the engineers working with cubesat hardware and software integration, and I've been following this project since 2023 because I agree that standardizing over Ethernet over (twisted pair, UART, single pair, etc...) will solve a lot of integration pain from all of the DIY protocols that the cubesat/smallsat community uses Some thoughts: - You actually have a publicly available ICD at https://github.com/the-aerospace-corporation/satcat5/tree/ma... , please publicize this more in the readme! You're a very rare exception in a world of contact us and sign an NDA first and commercial in confidence ICDs, which is great, and leads me to my next point: - Compared to HTTP API documentation, space ICDs sucks. One of the ICDs that I have put its protocol documentation as screenshots instead of copy pasteable text. Of course ICDs sucks b
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ecause you won't know its quality until you buy it... Anyway standardizing on ethernet for transport layer give you all the tooling at 99% of the world's computer use, and it might be a first step in making a OpenAPI / Swagger type tool but for space protocols - Any plans for 10base-T1S single pair ethernet? Our 6U cubesats barely have enough power to run its payload computers, let alone a FPGA based switch. But in a way a switched star network can be more reliable than a multidrop bus, as you can isolate babbling idiot nodes, and filter out accidental/intentional MAC/IP address spoofing
In Show HN: SatCat5, the open-source FPGA Ethernet switch
ooterness·Mar 16, 2024Submission

Show HN: SatCat5, the open-source FPGA Ethernet switch

We've just launched v2.5 of SatCat5, the open-source FPGA Ethernet switch [1]. SatCat5 contains various FPGA building blocks that let you build a custom mixed-media Ethernet switch. It was originally intended for cubesats [2] but has many other potential applications. The headline feature for this release is support for the IEEE-1588 Precision Time Protocol (PTP). SatCat5 has demonstrated end-to-end synchronization to within 50 ps-rms, which is approaching the world-leading performance of CERN's White Rabbit Project [3]. Except we're doing time-transfer over regular, non-synchronous Ethernet. The key breakthrough is a new technology for digital timestamps that we've published in IEEE Access [4]. This project was featured on HN back in 2023 [5]. Since then, we've changed to the CERN-OHL-W v2.0 license, which has much better legal clar
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ity for FPGA projects. [1] https://github.com/the-aerospace-corporation/satcat5 [2] https://digitalcommons.usu.edu/smallsat/2020/all2020/174/ [3] https://white-rabbit.web.cern.ch/documents/White_Rabbit-a_PT... [4] https://ieeexplore.ieee.org/abstract/document/10367970 [5] https://news.ycombinator.com/item?id=34817550
190 points · Open discussion

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