SLogic32U3 Software Guide

2026-10-22
Update history
Date Version Author Update content
2026-10-22 v0.4 Sipeed
  • Added a firmware update section, taking over the instructions migrated from the Hardware Guide
  • Converted callouts to blockquotes that teedoc can parse
2026-10-06 v0.3 Sipeed
  • Standardized on SLogicView as the default host app; removed PulseView references
  • Added the SLogicWeb web app with a UI screenshot
  • Rewrote ALL LOGIC around its DSView lineage as a fine community app
  • Added a host-app selection guide; reordered sections by host app
2026-10-06 v0.2 Sipeed
  • Restructured to the SLogic16U3 page layout; split out a standalone software guide

Software Guide

The SLogic32U3 can be driven by several host apps. This page helps you choose first, then covers each one. For wiring see the Hardware Guide; for first use see the Quick Start.

Pick a host app first

Use SLogicView by default. It is Sipeed's own, maintained GUI and the current direction; it is enough for the vast majority of debugging tasks.

Host app Strength Who it's for Install
SLogicView Sipeed's own, maintained GUI, the default Most people needs install
ngscopeclient GPU-accelerated rendering, Filter Graph, mixed signal complex analysis; ADC module as a scope needs install
sigrok-cli command line, scriptable automation, CI, headless capture, AI Agent needs install
ALL LOGIC a fine community app, built on DSView users familiar with DSView / DSLogic needs install
SLogicWeb (web) no install, no driver, Android support quick debugging, phone/tablet, no software no install

ALL LOGIC is a community project, built on top of DreamSourceLab's open-source DSView; Sipeed has contributed to it. If you are used to DSView it will feel right at home.

About "no install": desktop apps all need downloading and installing or unpacking first. The only thing you truly just open in a browser is the web app slogic.sipeed.com.

Supported platforms

Download

All desktop apps are in the same Release; pick the file for your platform:

Platform File suffix How to run
Windows 10/11 x64 -windows-x86_64.exe run directly
Linux x86_64 -linux-x86_64.AppImage chmod +x, then run
macOS (Apple Silicon) -macos-arm64.dmg open the dmg to run directly, or drag into Applications

SLogicWeb (web app)

Open slogic.sipeed.com and you are ready — the fastest way to start and the only truly download-free, install-free one.

SLogicWeb UI

The screenshot above is an actual capture with the SLogic32U3 connected in a browser: all 32 channels on, 200 MS/s real-time, the status bar showing 300 million samples received. The right panel sets sample rate, threshold, trigger and capture mode directly — no less capable than the desktop.

Features

  • No install, no driver: nothing to download, the browser connects the device directly.
  • Android support: open it in Chrome on a phone or tablet and capture — great in the field.
  • Remembered grant: the first connection shows a device picker; once authorized, the site remembers it.
  • Offline analysis: open existing .sr and .lwcap waveform files without a device attached.
  • Full-speed capture: 32 channels at 200 MS/s run just as fast in the browser; the web app is not a cut-down version.

Browser requirements

The web app talks to the device over WebUSB, so a Chromium-based browser is required:

  • Works: Chrome, Edge, Brave (desktop and Android)
  • Does not work: Firefox, Safari (no WebUSB)

If the page says WebUSB is unavailable in this browser, your browser is unsupported — switch to Chrome or Brave.

Steps

  1. Open slogic.sipeed.com in Chrome.
  2. Click Connect device, pick the SLogic16/32 U3 in the dialog and authorize it.
  3. Set sample rate, channels and threshold, then click Start.
  4. Use Fit to auto-zoom the waveform, Save to store a .lwcap.
  5. An existing waveform file can be loaded directly with Open….

SLogicView

💡 The decoder-list figures in the Protocol decoding section still use PulseView screenshots from the same code base (identical decoders and workflow); the rest are now actual SLogicView captures and screen recordings.

Connect the device

Best practice: connect the device to a USB3 port first, then launch the app so it auto-detects on startup.

If the app is already running, click Connect to Device, choose the driver, click Scan, then select the device found.

The main window has a few areas:

  • Top toolbar: device selection, capture depth, sample rate, run/stop, zoom and cursor tools
  • Left channel bar: channel on/off, color, voltage threshold
  • Center waveform area: waveform display, decode annotations
  • Decoder panel: add and configure protocol decoders

If no device is found, first check the ACT indicator is cyan. Blue only means the USB3 link is not established. On Linux also confirm the udev rule is installed. See the FAQ.

Stream capture

The SLogic32U3 uses Stream mode: data streams back to the host in real time, so capture length is unlimited in theory, bounded only by disk. The onboard 2 Gbit DDR3 acts as an elastic buffer to smooth USB jitter, sustaining 800 MB/s (6.4 Gbps) in practice.

This means no trade-off between "capture depth" and "sample rate" — you can capture continuously for a long time without being capped by device-side buffer size.

Sample rate vs channel count

Channels on Max sample rate Data rate
4 ch 1400 MHz 5.6 Gbps
8 ch 800 MHz 6.4 Gbps
16 ch 400 MHz 6.4 Gbps
32 ch 200 MHz 6.4 Gbps

8 / 16 / 32 channels all hit the 6.4 Gbps bandwidth ceiling; 4 channels are bounded by the 1400 MHz max sample clock.

Fewer channels on, higher sample rate available — but only in fixed groups; you cannot pick arbitrary channels:

  • 4 channels → fixed D0–D3
  • 8 channels → fixed D0–D7
  • 16 channels → fixed D0–D15
  • 32 channels → all D0–D31

The enabled set is always the contiguous low channels starting at D0. Arbitrary channel combinations are not supported (e.g. you cannot capture only D5, D10, D20 at a high rate). When wiring, connect the signals you want to capture fast to contiguous channels starting at D0.

For reference, the USB3.0-based DreamSourceLab DSLogic U3Pro32 in Stream mode is roughly 16ch@125MHz, 32ch@50MHz (per its public datasheet); the SLogic32U3 is 16ch@400MHz, 32ch@200MHz, about 3–4× the stream rate.

The clip above: switching the channel count (32 / 16 / 8 / 4) in the Configure panel changes the available sample rate.

Captured channels can be recolored, resized and reordered in the view so related buses sit together (display only, does not affect capture):

How to choose the sample rate

  • Rule of thumb: 10–100× the highest frequency of the signal.
  • Too low and you miss edges, distorting the waveform or failing the decode.
  • Too high and you capture meaningless glitches while using more memory and disk.
  • Sample rate × depth sets the storage used; confirm free disk before a long capture.

Voltage threshold

Set the logic decision threshold in the left channel bar, 0–6 V in 0.1 V steps. Below it = 0, above it = 1. For suggested thresholds per logic level see the Hardware Guide.

Triggers

The SLogic32U3 supports multi-channel, multi-edge combination triggers. You can set rising, falling, any-edge or level conditions per channel and combine them, and there is a pre-trigger to see what happened before the event.

Scenario Trigger setting
Catch one UART frame RX falling edge (start bit)
Catch an I²C transaction SDA falling while SCL high (start condition)
Catch an SPI chip-select cycle CS falling edge
Catch a reset anomaly RESET falling edge

Browsing and cursor measurement

Action How
Pan the view hold the left button and drag
Horizontal zoom (time) scroll wheel, or − / +
Horizontal pan (time axis) Shift + wheel, or Alt + wheel
Vertical pan Ctrl + wheel

Add cursors from the Cursors toolbar button, then measure the time between two points to derive baud rate, pulse width, event interval and so on.

Protocol decoding

150+ protocol decoders

Multi-protocol decoding

SLogicView decoding a live PWM signal.

The sigrok ecosystem offers 150+ protocol decoders covering I²C, SPI, UART, CAN, SDIO, 1-Wire, USB, Modbus and other common buses.

  1. Open the Decoder panel and choose the protocol.
  2. Configure the pin mapping, matching each decoder signal to the wired channel.
  3. Configure protocol parameters: baud rate, byte order, clock polarity/phase, CS polarity, etc.
  4. The decoded result overlays as annotations below the waveform; click for details.
  5. Decoders can be stacked — e.g. put eeprom24xx on top of I²C to read memory transactions directly.

Common reasons a decode fails:

Symptom Usually
No decode output at all wrong pin mapping, or wrong protocol params (baud, polarity)
Fragmented output, many errors sample rate too low; raise it and recapture
The waveform itself looks blocky/distorted threshold off, or sample rate too low
Occasional bad frames poor grounding; add a ground close by

Empty output only means the current config produced no annotations, not that there is no traffic in the waveform. Go back to the waveform and confirm the levels are changing.

File operations

  • Save session: saves samples, channel config, trigger and decoder state.
  • Export: CSV, VCD and more; VCD opens in GTKWave.
  • Import: load an existing .sr waveform directly; offline analysis needs no device.

ALL LOGIC (community project)

ALL LOGIC is a fine community-maintained host app, built on DreamSourceLab's open-source DSView (which itself derives from sigrok's PulseView).

Its idea is a multi-vendor universal host app: on top of the original DSView code it adds community drivers for various logic analyzers, so one app drives many devices on the market.

Who it's for: if you are already used to the DSView or DSLogic interface, ALL LOGIC works exactly the same — zero migration cost.

Supported devices include the Sipeed SLogic Combo 8 / 16U3 / 32U3, the CH32H417 open-source logic analyzer, PXLogic32U3, ALIENTEK ATK-Logic, nanoDLA / FX2 and more; the DreamSourceLab instruments DSView already supported still work.

Other features:

  • A built-in MCP interface, so an AI client can drive capture and decode directly.
  • Shares the libsigrok family of drivers and decoders with the official apps, so protocol coverage matches.

ALL LOGIC is community-maintained; report issues and requests on its project Issues.

ngscopeclient

For scenarios needing GPU-accelerated rendering, Filter Graph analysis and mixed-signal observation. For full install and connection see the ngscopeclient guide.

32U3 notes:

  • Single binary, all-UI config: just run it; connection, capture mode and parameters are all set in the UI.
  • Connect the device: add and select the SLogic device in the UI; once connected, the channel panel shows 32 channels.
  • Filter Graph: unifies protocol decode, math and measurement as Filter nodes you can chain.
  • ADC analog mode: once enabled in the UI, it merges digital pins into 4 analog channels A0–A3 (8-bit) for scope-style observation. Requires the optional ADC module.

sigrok-cli (command line)

For automation, CI and headless capture.

# scan devices
sigrok-cli --scan

# read device capability (supported sample rates, channels, etc.)
sigrok-cli -d sipeed-slogic-analyzer --show

# capture: only D0, 500k samples at 10 MHz, save as .sr
sigrok-cli -d sipeed-slogic-analyzer \
  --config samplerate=10m -C D0 \
  --samples 500k -o capture.sr

# decode an existing waveform
sigrok-cli -i capture.sr -P uart:rx=D0:baudrate=115200 -A uart

# export to VCD for GTKWave
sigrok-cli -i capture.sr -O vcd > capture.vcd

Common options:

Option Meaning
--config samplerate= sample rate, e.g. 10m, 200m
-C channels to enable, comma-separated, e.g. D0,D1,D2
--samples number of samples
--time capture duration (ms), alternative to --samples
--triggers trigger condition, e.g. D0=f for D0 falling edge
-P protocol decoder and its parameters
-o / -i output / input waveform file

Capture time (s) = samples ÷ sample rate. For example, 500k samples at 10 MHz is 50 ms.

Firmware Update

SLogic32U3 firmware is updated online with the web tool SLogic Firmware Update — nothing to download or install.

  • Browser: Chrome, Edge or another Chromium-based browser on a computer (updates use WebUSB, which Firefox and Safari do not support).
  • Driver: no driver is needed on Windows. On Linux, run the following once to allow your user to access the analyzer, then re-plug it (the page shows it too): 
    sudo tee /etc/udev/rules.d/60-slogic.rules >/dev/null <<'END'
SUBSYSTEM=="usb", ATTRS{idVendor}=="359f", ATTRS{idProduct}=="0300|3031|3032|30f1|30f2", MODE="0666", TAG+="uaccess"
END
sudo udevadm control --reload-rules && sudo udevadm trigger
  • USB cable: use a USB data cable plugged directly into the computer, not a charging-only cable or an unpowered hub. A 10 Gbps port is recommended; see Quick Start · Connect the device.
  • Firmware downloads: SLogic32U3 firmware (app.bin); future updates are published here too.

Update steps

  1. Download the latest firmware file.
  2. Open https://slogic.sipeed.com/ota/ in Chrome / Edge, connect the SLogic32U3 with a USB cable and click Select device.
  3. The page restarts the SLogic32U3 in update mode automatically (LED cyan with a slow red blink); select the update-mode device (usually shown as "SLogic DFU") in the browser dialog. You can also enter update mode by pressing the recessed MODE button with a pin; see Hardware Guide · MODE Button.
  4. Choose the downloaded firmware file and click Update firmware. Keep the device connected and the page open until the update finishes.
  5. When the update finishes the device restarts with the new firmware (LED steady cyan) and returns to APP mode.

In principle the update only replaces the SLogic firmware and never touches the DFU (update-mode) function. Even if an update fails, the device stays in update mode — keep it connected and run the update again.

Known Limits

Limit Notes
Trigger (ngscopeclient) the ngscopeclient integration currently supports single-channel, single-edge triggers only. For multi-channel or multi-edge combinations use SLogicView or sigrok-cli
Rate drops with channel count 8 / 16 / 32 channels already hit the 6.4 Gbps ceiling and cannot go higher; trade channels for a higher rate
Long capture bounded by disk Stream mode is unlimited in theory, but rate × depth directly sets disk usage
Web app browser requirement SLogicWeb relies on WebUSB; Firefox and Safari do not work
ADC with digital capture the optional ADC module takes the corresponding digital pins; whether both run together depends on channel allocation, go by the actual unit

AI Agent integration

With sigrok-cli-slogic-plugin, you can let an Agent run scan, capture and decode for you in natural language. See the full guide at SLogic with an AI Agent.