Serial Monitor

A desktop serial monitor for embedded development — built with Tauri 2, React, and Rust. Targets Teensy, Arduino, ESP32, and any other device that communicates over a serial port.

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Features

Monitor

• Real-time serial receive display, virtualized for high-throughput streams (up to 1.5 Mbaud+)
• Send text or raw hex bytes with configurable newline (LF / CRLF / CR / none)
• Timestamps per line, auto-scroll, manual freeze
• Sent-message history side panel
• Secondary monitor panel for side-by-side channel views

Plotter

Auto-discovers graph channels from serial output — no configuration needed. Any line matching key: value1, value2, ... creates or updates a channel named key. Supports four panel types per channel:

Panel type	Use case
Time series	Waveforms, sensor readings over time
XY scatter	Lissajous figures, parametric curves
FFT	Frequency spectrum from a continuous signal
Bar	Live bar chart for slow-changing values

• Configurable time window (1 s – 60 s)
• Per-series color, Y-axis limits, enable/disable
• Pause, zoom (X / Y / both), pan, reset
• Sync zoom across all panels

Commands

• Save serial commands with a name, payload (text or hex), and group
• Drag-and-drop reorder within and across groups
• Run All executes an entire group in sequence, with optional delay steps between commands
• Select a group to target where new commands are added

General

• Light / dark / auto theme
• Memory usage side panel (lines buffer + plot buffer stats)
• Full keyboard shortcut system (press ⇧? to see all shortcuts)
• Persistent panel state across view switches

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Plotter format

Print lines from your firmware in this format:

graphName: series1=value, series2=value

or, for a single series:

graphName: value

Examples:

// Single value → one series
Serial.print("temperature: ");
Serial.println(temp, 2);

// Multiple values → multiple series on the same graph
Serial.print("imu: x=");  Serial.print(ax);
Serial.print(", y=");     Serial.print(ay);
Serial.print(", z=");     Serial.println(az);

// Lines without a "key: value" pattern are shown in the monitor but ignored by the plotter
Serial.println("System OK");

Lines starting with # are treated as comments. The = sign in values is optional — key: 1.0, 2.0 and key: a=1.0, b=2.0 both work.

See test.ino for a full working example covering all four panel types.

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Download

Pre-built binaries are attached to each GitHub Release.

Platform	File to download
macOS (Apple Silicon + Intel)	Serial Monitor_*_universal.dmg
Windows 64-bit	Serial Monitor_*_x64-setup.exe

These builds are unsigned. Both platforms will show a one-time security warning.

macOS — bypassing Gatekeeper

After opening the .dmg and dragging the app to Applications, macOS may refuse to open it.

Option 1 — right-click method (easiest):

1. Right-click Serial Monitor.app in Applications
2. Click Open
3. Click Open again in the dialog

Option 2 — remove quarantine flag:

xattr -dr com.apple.quarantine "/Applications/Serial Monitor.app"

Then open normally.

Windows — bypassing SmartScreen

When you run the installer, Windows may show "Windows protected your PC":

1. Click More info
2. Click Run anyway

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Build from source

Building locally avoids all signing/quarantine issues — macOS and Windows treat locally-built apps as trusted.

Prerequisites

All platforms:

• Rust (stable toolchain)
• Node.js 18 or later

macOS only:

xcode-select --install

Windows only: Install the Microsoft C++ Build Tools. During setup, select Desktop development with C++.

Build

git clone https://github.com/seanboerhout/serial-monitor.git
cd serial-monitor
npm install
npm run tauri build

The first build takes 5–15 minutes (Rust compile). Subsequent builds are much faster.

Install the built app

macOS:

src-tauri/target/release/bundle/dmg/Serial Monitor_*.dmg

Open the .dmg and drag to Applications. Or use the .app directly from bundle/macos/.

Windows:

src-tauri\target\release\bundle\nsis\Serial Monitor_*_x64-setup.exe
src-tauri\target\release\bundle\msi\Serial Monitor_*_x64_en-US.msi

Run either installer. The NSIS .exe is a standard installer wizard; the .msi is for enterprise/group policy deployment.

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Keyboard shortcuts

Press ⇧? inside the app to see all shortcuts. Common ones:

Shortcut	Action
⇧M	Monitor view
⇧P	Plotter view
⇧D	Commands view
⇧C	Connect / disconnect
⇧X	Clear display
⇧H	Toggle sent-history panel
⇧I	Toggle memory panel
⇧?	Toggle shortcut hints
Esc	Close open panels

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Development

npm install
npm run tauri dev

The dev server runs at http://localhost:1420 with hot-reload for the frontend. Rust changes trigger a recompile automatically.