Sigphase
Sigphase · Product 01

One box,
many bench tools.H-Agent S1 (working name)

A compact touchscreen Linux computer that puts a debug probe, functionally isolated bus adapters and a bus-servo driver in one box. It's designed for your AI to drive: the AI runs on your computer, LAN server or cloud account, and the box powers, flashes and listens to your hardware over Wi-Fi.

Follow the build See progress
Status Design complete; prototype boards not yet ordered.
Render of H-Agent S1 (working name) from the front right. A light-grey top cover with the touchscreen (screen off) and two speaker grilles sits on a dark-grey base. The front has two debug ports and the USB-C mode switch; the right side has the servo, CAN FD, RS-485 and RS-232 terminals and the USB-A host port. Render
3.97″480 × 800 touchscreen
2multi-protocol debug ports
3 busesRS-485 · RS-232 · CAN FD
6–26 VDC input (design)
115 × 80 × 40 mmenclosure (design)
Port tour

Every side does a job.

Pluggable terminals for the buses, two debug ports at the front, power on the left. Click through each side.

Render of the front side: debug ports A and B, two 10-pin pluggable terminal headers with a custom pinout. A small window on the left shows the USB-C mode switch.Render
  1. Debug port AJTAG / SWD / SPI / I2C / UART, switchable 3.3 V or 5 V target power with current sensing. Shared with the servo port.
  2. Debug port BSame protocols and target power, always available for sensors or a second target.
  3. USB-C mode switchSelects console or service mode for the USB-C port on the left side.
A real computer

A Linux computer you can carry to the bench.

Underneath the ports is a complete, practical Linux machine: quad-core processor, touchscreen, Wi-Fi, speakers, microphones and a 6-axis motion sensor, in a 115 × 80 × 40 mm box (design).

  • Quad-core Cortex-A53, 1 GHz, 512 MB · designed to run Raspberry Pi OS*
  • 3.97-inch 480 × 800 capacitive touchscreen · set up Wi-Fi and see the device address without a PC (planned)
  • Two microphones, stereo speakers, headphone jack
  • Dual-band Wi-Fi module · rated 802.11ax by its maker, not yet verified
  • Camera connector · camera sold separately
  • 1S battery input · battery not included; buy a protected pouch cell locally
Render of the underside, with the unit turned over: the battery door (battery not included), four rubber feet, four M3 inserts 100 × 45 mm apart (design), the camera mounting area with its cable slot (camera sold separately) and ventilation slots.Render
One box, many bench tools

Probe, bus adapters and servo driver, together.

The debug ports give you programmable, current-limited target power with current sensing, target reset and software-selected protocols. Next to them sit functionally isolated field buses and a bus-servo port. One box, one power supply, one network address.

  • 2 debug ports: JTAG, SWD, SPI, I2C, UART · open-source OpenOCD, board configuration in development
  • 3.3 V / 5 V target power, about 0.3 A per port · calculated
  • RS-485 and RS-232 in one isolation domain, CAN FD in another · functional isolation, not safety insulation
  • Used over Wi-Fi · it is not a USB probe for your PC
Render of H-Agent S1 wired up on a bench. Five jumper wires run from debug port A to a small target board, a power cable sits in the DC input terminal, and CAN FD and RS-485 cables leave from the right side. The cables and the target board are illustrative.
Listen first, then write

See the bus before you touch it.

RS-485 receives by default and CAN can run listen-only, so you see existing Modbus and CAN traffic before anything is sent. With a planned DB9 cable, the RS-232 port brings serial bench instruments onto Wi-Fi.

Design; software in development. For benches, indoor pilots and short field sessions, not permanent installation. Field devices need their own power supply.

Render of H-Agent S1 on a workbench, with a three-core cable from its RS-485 terminal to a Modbus RTU panel meter on a DIN rail. A small circuit breaker and a 24 V supply for the meter sit on the same rail above a wiring duct. The panel parts and wiring are illustrative.
Designed for AI Experimental

The AI stays on your side.

H-Agent S1 doesn't contain an AI model. It gives the AI coding agent you already use documented hands on real hardware, and keeps you in charge of anything risky.

Bring your own agent

Markdown packs and a CLI

Markdown instruction packs and a command-line interface let your desktop AI agent drive the ports over SSH. The CLI and Python library also work without any agent. (In development.)

Guard rails

Risky actions wait for your OK

First power-up of a new target, the first switch to 5 V and transmitting on an unknown bus wait for confirmation on the touchscreen. (Planned.)

No lock-in

No account with us

No subscription. AI services are paid directly to your provider.

Privacy

Opt-in only

Telemetry and update checks stay off until you opt in. The power co-processor can cut power to the mics and camera. (Planned / design.)

Security

No default password

You set your own password at first boot. (Planned.)

On H-Agent S1

Touchscreen UI, port control with approval rules, power telemetry, photo capture. A wake word and small models may fit; to be measured. (Planned.)

Your computer or LAN server

Large language models, speech recognition and text-to-speech, vision models and firmware builds.

Your cloud account

LLM, speech and vision APIs with your own key. You pay your provider directly.

Planned architecture; software in development. Running large language models on the device is not claimed.

Use cases

From the firmware bench to the robot desk.

Four bench jobs it's designed for. The scenes are renders; the cables, panels and props are illustrative.

Render of H-Agent S1 wired to a small target board with jumper wires from debug port A, plus CAN FD and RS-485 cables.
Flash and debug a targetPower the target, flash it, reset it, read its UART and measure its current from one place.
Render of H-Agent S1 connected by a three-core cable to a Modbus RTU panel meter on a DIN rail.
Field buses and instrumentsListen to Modbus RTU and CAN traffic, then talk to meters, sensors and relays once you approve.
Render of H-Agent S1 driving a pan-tilt head made of two TTL bus servos with a USB camera on top, aimed at a red ball.
Bus servos and visionDrive TTL bus servos and use a USB camera for example projects such as a look-around head. PWM servos aren't supported.
Render of H-Agent S1 on a desk mat next to a laptop and a mug, powered through its DC barrel jack, screen off.
A Linux box on your deskA small touchscreen Linux computer with audio and Wi-Fi for your own apps. Speech and language models run on your computer, LAN server or cloud account.
Exploded render, top to bottom: top cover, touchscreen and display, display frame, audio board with its two speakers, main board, standoffs, and the bottom cover with the battery door and screws. No battery and no camera are shown; neither is in the box.Render
Inside

Two boards, one tidy stack.

A main board with the compute module, power system, debug and bus interfaces, and an audio board under the display. An always-on STM32 power co-processor watches input voltage, battery, temperature and per-port current, and can switch the Linux side off entirely.

  • Input over-voltage, reverse-polarity, surge and current-limit protection · design, prototype testing pending
  • High-risk outputs off at power-up; four outputs individually switchable with current sensing
  • Four M3 inserts on the bottom, 100 × 45 mm apart · for 3D-printed mounts
Specifications

The details.

Values are from the current design (main board rev 4e, audio board A2, enclosure v3r6). Calculated and datasheet figures are marked; measured values will follow prototype testing.

Compute

Processor
Quad-core Cortex-A53, 1 GHz (datasheet)
Memory
512 MB
Storage
microSD boot
OS
Designed to run Raspberry Pi OS*
Co-processor
STM32 power and telemetry controller

Display & audio

Touchscreen
3.97-inch, 480 × 800, MIPI DSI, capacitive touch (design)
Video out
mini-HDMI
Audio
2 microphones, stereo speakers, 3.5 mm headphone jack (design)
Camera
CSI-2 connector; camera sold separately

Debug ports

Ports
2 (port A shared with the servo port); custom pinout
Protocols
JTAG, SWD, SPI, I2C, UART (datasheet)
Target power
3.3 V / 5 V, about 0.3 A per port (calculated)
Current sensing
About 0.4 mA resolution (design)
Target I/O level
1.1–5.5 V, follows target reference (datasheet)

Functionally isolated buses

RS-485
Half-duplex, receive by default (design)
RS-232
250 kbit/s guaranteed (datasheet)
CAN FD
Classic up to 1 Mbit/s, FD data phase up to 5 Mbit/s (datasheet); listen-only mode
Isolation
RS-485/RS-232 in one domain, CAN FD in another; functional isolation, not safety insulation

Bus-servo & USB

Servo port
TTL bus servos, 3.3 V half-duplex; 5 V (1.49 A limit) or input pass-through (2.98 A limit, needs ≥9.5 V input) (calculated)
USB-A
USB 2.0 host, 0.5 A rated, switchable
USB-C
Service port: serial console or service mode

Power, wireless & mechanical

DC input
6–26 V (design); barrel jack or terminal
Backup input
USB-C 5 V (no PD)
Battery
1S input with charger; battery not included
Wireless
Dual-band Wi-Fi module rated 802.11ax by its maker (not yet verified); Bluetooth hardware reserved
Sensors
6-axis IMU; input, battery and per-port current monitoring
Size
115 × 80 × 40.3 mm (design)
Enclosure
3D-printed (prototype)

What it is not

Honest limits, so you can decide early.

Not a breadboard GPIO toolNo general-purpose GPIO, PWM or analog inputs; add I2C modules for those.
Not an LLM boxLarge models run on your computer, server or cloud account.
No EthernetNetworking is Wi-Fi only.
Not for mains switchingDon't use it to switch mains loads.
Not a long-runtime handheldRuntime figures will be published only after measurement.
Not for permanent installs yetOperating temperature and protection rating aren't defined.
Open source

Open-source release planned.

We plan to release schematics and KiCad files, the enclosure CAD, the STM32 firmware, and the device service, command-line tools and AI instruction packs. Licences will be named before launch. Third-party parts such as the compute module and the Wi-Fi module firmware are not open and will be listed in the docs.

  • Schematics & KiCad PCB · licence to be decided
  • Enclosure CAD & printable brackets
  • STM32 firmware · signed release builds, unlockable
  • CLI, Python library, Markdown packs
  • Docs & test procedures
Progress

Where the project stands.

Updated as milestones land. Future dates are plans and will move if prototype testing finds problems.

Done · 2026

Hardware design complete

Main board through its fourth revision (4e), audio board A2 and enclosure v3r6. Production files exported; renders from the CAD assembly.

Now · Nov 2026

Prototype boards

Order, assemble and power up the first boards, then run basic function tests. Target: by the end of November.

Planned · Dec 2026

Bring-up and first demos

Linux, touchscreen, Wi-Fi, audio and camera running on real boards, then a first AI-in-the-loop debugging demo, docs v0 and a public repository.

Planned · Dec 2026

Crowdfunding application

Apply to a crowdfunding platform for engineering hardware with working-prototype evidence.

Planned · Jan 2027

Pre-launch page and enclosure first articles

Real photos replace renders; testers and reviewers get early units.

Planned · after Chinese New Year 2027

Campaign launch

A small production run for certification testing during the campaign, so shipping can start soon after it ends.

Follow the build

Be there when the first board powers up.

Build notes cover what we built, what we measured and what's next, plus the road to the campaign. Nothing here is for sale: no orders, deposits or reservations.

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* Raspberry Pi is a trademark of Raspberry Pi Ltd.