ai4chat.co, 2 chats attached, third pasted below
Hi gpt-5 mini via ai4chat.co, do you know anything about open hardware
capable of reading usb traffic like maybe the greatfet? Do you also
know of any cdrom or usb storage devices associated with open source
efforts? Can you list things with prices? I’d like something cheap
with an active development community.
Yes — there are several open-hardware / open-source-friendly options
for reading or otherwise interacting with USB traffic. Which one is
best depends on what you mean by “read USB traffic” (passive low-level
sniffing of the differential pair, MITM sniffing/modifying, or
emulating devices/storage), and which USB speed you need
(low/full-speed 1.5/12 Mbps vs high-speed 480 Mbps). Below is a
concise catalog with approximate prices, capabilities, and notes about
community activity.
Quick notes up front
- Passive, bus‑level sniffing of USB 2.0 High‑Speed (480 Mbps) is hard
to do with cheap hardware. Most inexpensive open solutions cover
low/full speed (1.5/12 Mbps) or do MITM sniffing at the USB protocol
layer (host/gadget) rather than raw differential-line capture. If you
need true 480 Mbps bus capture you’ll likely need a commercial
analyzer (Total Phase Beagle, Ellisys, LeCroy, etc.).
- Prices vary by seller and region; below are approximate retail
ranges (2024-era). Always verify current prices before buying.
Open-hardware / open-source friendly tools (shortlist)
1) GreatFET One
- What: Open-hardware USB development/hacking board from Great Scott
Gadgets. Good for USB device emulation, USB fuzzing, low-level
control, interacting with USB peripherals from Python.
- Speeds: Works as a USB device and can be used for host/emulation
tasks; not a drop-in passive HS sniffer. Good for device-logic hacking
and software-level USB work.
- Price: ~$150–$200.
- Community: Active (Great Scott Gadgets, GitHub, forums).
- Good for: Emulating devices, fuzzing, experimenting with USB stacks
and device firmware.
2) Facedancer (with a cheap Cypress FX2 dev board)
- What: Facedancer is an open-source tool for USB device emulation and
crafting frames. Originally used with GoodFET/FX2 boards. You use a
Facedancer-capable board (Cypress FX2LP dev boards are common) to
emulate many USB devices.
- Speeds: FX2 is full-speed / high-speed capable for emulation; but
again this is device emulation, not passive HS bus sniffing.
- Price: FX2 board ~$15–$40; Facedancer is software (free). Some
vendors sell Facedancer-ready boards.
- Community: Active in niche USB-hacking circles (GitHub repos, Great
Scott Gadgets pages).
- Good for: Emulating mass-storage, HID, or custom devices for testing.
3) Raspberry Pi Zero W / USBProxy (MITM)
- What: Pi Zero (OTG) running usbproxy or usbip or custom gadgetfs
code to act as a man‑in‑the‑middle between a host and device — you can
capture, log, and modify USB traffic.
- Speeds: Pi Zero provides USB OTG at full-speed (12 Mbps); cannot
handle high-speed 480 Mbps.
- Price: Pi Zero W ~ $10–$20 (plus SD card, power).
- Community: Very active; many USB gadget examples, usbproxy forks,
and tutorials.
- Good for: Cheap MITM sniffing/modifying for low/full-speed devices,
USB mass storage/CD-ROM gadget emulation (see below).
4) Fomu (open FPGA USB stick)
- What: Tiny open-source FPGA board that plugs into a USB-A port and
can act as a USB device. Good for building custom USB devices and
low-level experiments.
- Speeds: Primarily for device development (FS/LS or limited HS
depending on design).
- Price: ~$30–$50.
- Community: Active indie/hobby FPGA and USB device community.
- Good for: Device emulation, custom USB peripherals, proving concepts.
5) Raspberry Pi Pico / RP2040 (TinyUSB) and Teensy
- What: Microcontroller boards (RP2040, Teensy) with TinyUSB stack can
present USB Mass Storage, CDC, HID, etc. Many examples show presenting
a file as a CD-ROM image or an MSC device.
- Speeds: Full-speed (12 Mbps) for Pico/Teensy depending on model;
some Teensy variants support higher performance.
- Price: Pico ~$4; Teensy ~$20–$30.
- Community: Very active (Raspberry/Adafruit/Paul Stoffregen communities).
- Good for: Emulating USB storage/CD-ROM devices cheaply for testing.
6) Logic analyzer approach (Sigrok-compatible / Saleae and clones)
- What: Generic logic analyzers (Saleae, Sigrok-compatible devices)
can sample the D+ and D- differential lines and let you decode USB
1.1/2.0 signals if sampling rate and front-end are adequate.
- Speeds: Full-speed (12 Mbps) is feasible with modest analyzers
(sample >= 24–50 MS/s); high-speed (480 Mbps) needs very high sample
rates and proper differential front-end (expensive).
- Price: Official Saleae models: ~$199–$350; many clones / low-cost
logic analyzers: $20–$60. DSLogic / Bitscope / other mid-range
analyzers: $80–$200.
- Community: Strong (sigrok, Saleae community). sigrok has USB
decoders and extensive docs.
- Good for: Capturing low/full-speed bus signalling (needs correct
probing/termination), decoding lower-level timings, bit-banging
traces. Cheap but requires correct probing and sometimes hardware
modifications.
7) Beagle USB 480 (Total Phase) — commercial
- What: A widely used, reliable USB 2.0 protocol analyzer (non-open
hardware but very usable) with free viewer and plugin support.
- Speeds: Supports real-time USB 2.0 HS monitoring up to 480 Mbps.
- Price: ~$300–$700 depending on model (Beagle USB 480 v2 historically
around $299–$399).
- Community: Strong commercial support + many community examples.
- Good for: Real HS passive sniffing without breaking the bus — a
solid choice if you need real HS captures and aren’t tied to strict
open‑hardware requirement.
8) OpenVizsla (historic)
- What: An older open-source USB analyzer/sniffer project (USB 2.0).
Good conceptually but project activity has been spotty; hardware
availability limited.
- Price: Historically $50–$150 (if you can find hardware or build it).
- Community: Was active then slowed; check current repo/activity before buying.
- Good for: If you can find an active fork or parts, might be useful
for tinkering.
Open-source projects for CD-ROM / USB mass-storage emulation
- Linux USB Gadget (g_mass_storage, g_file_storage, gadgetfs,
configfs): you can make a Linux device (Pi, PC) present a file or ISO
as a USB CD-ROM or MSC device. Extremely common and well-documented.
- Raspberry Pi Zero W / Pico / Teensy + TinyUSB: many examples showing
how to present a USB mass-storage device or a CD-ROM (by presenting an
ISO image) — cheap and very active community.
- USB Armory / USBArmory Mk II: small open-hardware USB computer that
can act as a gadget and present mass storage or execute complex
gadgets. Price higher (~€100+).
- OpenSSD / academic SSD open firmware projects: aimed at SSD
controller research; hardware is specialist and not cheap. Mention
only if you’re doing SSD firmware research.
Recommendations based on what you said (cheap + active community)
- Cheapest MITM/sniffing for practical work (low/full-speed):
Raspberry Pi Zero W + usbproxy or Linux gadget-based capture. (Cost
~$10–$30)
- Cheapest device-emulation / storage/CD-ROM emulation: Raspberry Pi
Zero or Pico (TinyUSB) or Teensy for device emulation. (Pico $4;
Teensy ~$20–$30)
- Best open-hardware USB hacking board with active community: GreatFET
One (~$150–$200).
- If you need real HS passive sniffing: consider a commercial Beagle
USB 480 (~$300–$700) or a used Ellisys/LeCroy if available.
If you tell me:
- Which USB speed(s) you need to capture (LS/FS/HS),
- Whether you need passive capture (tap the D+/D- lines) or MITM (host↔device),
- If emulation of storage (virtual CD-ROM/ISO) or device fuzzing is your goal,
I’ll recommend the single best, cheapest hardware+software stack and
give buying links / step-by-step setup notes.
User:
Test
AI Assistant:
It seems like you're testing the system. How can I assist you
today? If you have any specific questions or tasks in mind, feel free to let me
know!
User:
Hi AI4Chat. Do you know anything about open hardware low-level
usb bus tools, like the great feat, cynthion, or Glasgow? Can you list them
alongside their chips, the usb standard they support, the bitrate of that
standard and that they read, and their price? I’m considering a usb sniffer to
help me sort my hardware glitches out.
AI Assistant:
I can provide a brief overview of the open hardware low-level
USB bus tools you've mentioned. However, I might not have the most current
details on prices or specific specifications, as these can frequently change.
Here’s a rundown:
Open Hardware USB Tools
GreatFET
Chip: ATSAMD51 (Arm Cortex-M4)
USB Standard: USB 2.0
Bitrate: 480 Mbps (high-speed)
Price: Typically around $100 (check the latest prices)
Cynthion
Chip: Various options; typical usage with Arm Cortex processors.
USB Standard: USB 2.0
Bitrate: 480 Mbps (high-speed)
Price: Around $150 to $200 (please verify updates)
Glasgow
Chip: Xilinx FPGA (varies with configurations)
USB Standard: USB 3.0 (also supports USB 2.0)
Bitrate: 5 Gbps (super speed) for USB 3.0; 480 Mbps for USB 2.0
Price: Approx. $99 to $150 (check current offerings)
Summary Table
Tool
Chip
USB Standard
Bitrate
Price Range
GreatFET
ATSAMD51
USB 2.0
480 Mbps
~$100
Cynthion
Various (Arm Cortex)
USB 2.0
480 Mbps
~$150 - $200
Glasgow
Xilinx FPGA
USB 3.0, 2.0
5 Gbps (3.0), 480 Mbps (2.0)
~$99 - $150
Before making your decision, it's best to verify the latest specifications and
prices from the manufacturers or retailers. If you have any other questions or
need more information, feel free to ask!
User:
Do you know of other usb hardware sniffers? Do you know if
anybody has made a discrete/ttl sniffer that could be hand-explored for any usb
portions?
AI Assistant:
Yes, there are several other USB hardware sniffers available in
addition to those mentioned earlier. Here are a few notable ones:
Other USB Sniffers
USBlyzer
Type: Software-based USB sniffer
Usage: Works in conjunction with USB devices on Windows platforms.
Note: Not hardware, but a powerful software tool for USB traffic analysis.
Total Phase Beagle USB 480 Protocol Analyzer
Chip: Custom chip
USB Standard: USB 2.0
Bitrate: 480 Mbps
Price: Around $299
Note: Widely used for protocol analysis.
BusPirate
Chip: Microchip PIC24
USB Standard: No direct USB sniffing, but supports various protocols.
Note: Low-cost multi-protocol tool often used for debugging.
ELM327 (primarily for automotive use)
Chip: ELM Electronics ELM327
Usage: Can be adapted for more general USB communications.
Note: Accompanied by software for data analysis.
Discrete/TTL USB Sniffers
As for discrete or TTL-based USB sniffers, there are a few DIY projects and
open-source designs that you might be interested in exploring:
USB Protocol Analyzer Circuit
Various DIY projects available on platforms like GitHub can lead you to
discrete solutions that can sniff USB lines. These often involve using
microcontrollers or FPGAs.
Bus Pirate's USB Mode
While primarily a multi-protocol tool, some users have managed to implement
UART or GPIO-based sniffing by adapting Bus Pirate’s capabilities.
FTDI based Sniffers
Some hobbyists design USB sniffers using FTDI chips because they can be
programmed to act as simple USB interfaces.
Resources for Custom Sniffers
Look for open-source projects on platforms like GitHub or forums focused on USB
hardware development, where enthusiasts share their designs and findings.
For hand-explorable solutions, USB sniffer boards may have available test
points and headers for probing and further exploration.
If you're interested in any specific designs or projects, I can help you find
more detailed information or resources!
