pineTERM|

A modern, browser-based serial terminal for UART communication with microcontrollers, embedded devices, and IoT hardware. No installation required - just open in your browser and connect to your serial device.

"pineTERM" is an independent project. Any similarity to other software names is coincidental.

Features

• Native Web Serial API - Direct hardware communication without native applications
• HEX and ASCII View Modes - On-the-fly switchable HEX and ASCII terminal views with synchronized scrolling
• Day/Night Themes - Switch between dark and light modes with persistent preferences
• Smart Input Handling - Auto-formatting HEX input with real-time validation
• JSON Command Sequences - Automated testing with programmable command batches
• Packet Timing Control - Intelligent frame detection based on inter-byte timing
• Log Export - Save terminal output as timestamped text files
• Responsive Design - Works on desktop and tablet browsers
• Dynamic input fields - add as many HEX and ASCII fields as you need, each with its own send button
• Custom baud rate support - set the baud rate you need, not need to be only standard

Quick Start

Requirements

• Chrome 89+, Edge 89+, or Opera (desktop only)
• USB-to-Serial adapter or native serial port
• Target device (Arduino, ESP32, Raspberry Pi Pico, etc.)

Live Demo (No Installation Required!)

Use it right now: https://wespeakenglish.github.io/pineTERM/

Simply open the link above in a supported browser, click "Connect to UART", and select your device. That's it!

Local Installation (Optional)

If you prefer to run locally:

git clone https://github.com/wespeakenglish/pineTERM.git
cd pineTERM
# Open index.html in Chrome/Edge/Opera

Basic Usage

1. Connect: Click "Connect to UART" → Select your serial port → Configure baud rate
2. Send Data: Type HEX (48 65 6C 6C 6F) or ASCII (Hello) and click send
3. Monitor: View responses in both HEX and ASCII tabs
4. Export: Click "Export log" to save the session

JSON Command Sequences

pineTERM supports automated command sequences via JSON files for testing and batch operations.

JSON Schema

[
  {
    "type": "ascii",
    "data": "AT+GMR",
    "times": 1,
    "preDelay": 0,
    "postDelay": 100
  }
]

Field Reference

Field	Type	Default	Description
type	string	required	"ascii" for text commands, "hex" for raw bytes
data	string	required	Command payload. For hex: space-separated bytes (e.g., "FF FE 01 00")
times	integer	1	Execution count: 0=skip, 1=once, N=repeat N times, -1=infinite loop
preDelay	integer	0	Milliseconds to wait before sending this command
postDelay	integer	100	Milliseconds to wait after sending (inter-command gap)

Example: WiFi Module Configuration

[
  { "type": "ascii", "data": "AT\r\n", "times": 0 },
  { "type": "ascii", "data": "AT+GMR\r\n", "times": 1, "postDelay": 500 },
  { "type": "ascii", "data": "AT+CWMODE=1\r\n", "times": 1, "postDelay": 1000 },
  { "type": "ascii", "data": "AT+CWJAP=\"MyNetwork\",\"MyPassword\"\r\n", "times": 1, "preDelay": 200, "postDelay": 5000 },
  { "type": "hex", "data": "FF FE 01 00", "times": 3, "postDelay": 300 },
  { "type": "ascii", "data": "PING\r\n", "times": 5, "postDelay": 1000 },
  { "type": "hex", "data": "AA 55 0D 0A", "times": -1, "preDelay": 50, "postDelay": 50 }
]

Command Flow:

1. Skip test command (times: 0)
2. Get firmware version, wait 500ms
3. Set station mode, wait 1s
4. Connect to WiFi with 5s timeout for connection
5. Send raw bytes 3 times with 300ms gaps
6. Send PING 5 times with 1s intervals
7. Infinite heartbeat loop (50ms delays)

Loading JSON Files

1. Click "Select JSON" in the Send Command panel
2. Choose your .json file
3. Click "Send JSON Commands" to execute
4. Click "Stop" to halt execution

Configuration Options

Serial Parameters

Setting	Options	Default
Baud Rate	9600 - 921600	9600
Data Bits	7, 8	8
Stop Bits	1, 2	1
Parity	None, Even, Odd	None
Flow Control	None, Hardware	None

Line Endings

Choose transmission termination:

• CR LF (\r\n) - Windows/DOS style
• LF (\n) - Unix/Linux style
• CR (\r) - Classic Mac style
• None - Raw data only

Packet Timing

Enable "Separated less than X milliseconds treat like one package" to:

• Buffer rapid incoming bytes into single log entries
• Prevent frame fragmentation
• Default: 10 ms threshold

Security & Privacy

• User Permission Required: Browser prompts for serial port access each session
• No Data Transmission: All communication stays local between browser and device
• No Storage: Logs are not saved unless explicitly exported by user
• HTTPS Required: Web Serial API requires secure context (localhost or HTTPS)

Browser Compatibility

Browser	Support	Notes
Chrome 89+	Full	Windows, macOS, Linux, ChromeOS
Edge 89+	Full	Windows, macOS, Linux
Opera	Full	Windows, macOS, Linux
Firefox	With addon	Windows, macOS, Linux with addon
Safari	None	Not supported
Chrome Android	via RFCOMM	USB serial OTG not supported

Use Cases

• Embedded Development - Debug Arduino, ESP8266/32, STM32 firmware
• IoT Prototyping - Test AT command sets on WiFi/BLE modules
• Hardware Testing - Automated regression testing with JSON sequences
• Reverse Engineering - Analyze proprietary serial protocols
• Education - Teach serial communication without complex tools

Troubleshooting

Issue	Solution
"Web Serial API not supported"	Use Chrome/Edge/Opera desktop, check version 89+
Device not appearing	Install USB-to-Serial drivers (CH340, CP2102, FTDI, etc.)
Garbled text	Verify baud rate matches device configuration
JSON commands fail	Validate JSON syntax, check console for errors

Contributing

Contributions welcome! Please:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit changes (git commit -m 'Add amazing feature')
4. Push to branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Acknowledgments

• Built with vanilla JavaScript- no frameworks, no dependencies
• Uses the Web Serial API standard
• Inspired by classic terminal emulators and modern web technologies

Made with 💙 for hardware hackers