IoT Serial Monitor

The IoT Monitor panel in AI Code Express (ACE IDE) is a built-in USB serial terminal. Use it to read live output from microcontrollers, edge devices, and sensors—and send commands back—without leaving your editor.

When to use it

• Firmware log inspection — Watch boot messages, stack traces, and debug prints as your device runs.
• Device bootstrap validation — Confirm the board enumerates and prints the expected startup sequence.
• Runtime diagnostics — Monitor temperature, signal strength, latency, or custom telemetry during field testing.
• Protocol debugging — Switch to HEX view when you need to inspect binary frames or raw bytes.

Pair serial output with the regular Terminal tab (builds, flashes, tests) and Run workflows for faster root-cause analysis.

Open the IoT Monitor

1. Open AI Code Express and load your project folder.
2. Open the bottom panel if it is hidden (Ctrl/Cmd + J or Terminal → Show Terminal Panel).
3. Click the IoT Monitor tab, or choose Terminal → IoT Monitor from the menu bar.

The status badge shows iot connected or iot disconnected when this tab is active.

Step-by-step: connect a device

1. Plug in your hardware

Connect the device over USB (Arduino, ESP32, Raspberry Pi Pico, STM32 dev board, USB–serial adapter, etc.). Ensure any vendor drivers are installed if your OS requires them.

2. Refresh the port list

Click Refresh. ACE scans for available serial ports and shows each path with optional manufacturer and vendor/product IDs (for example /dev/ttyUSB0 or COM3).

If no devices appear:

• Check the USB cable and port.
• Confirm the device is powered and not stuck in a bootloader-only state (unless that is expected).
• On Linux, verify your user has permission to access the serial device (see Troubleshooting).

3. Choose baud rate

Select the baud rate your firmware uses. 115200 is the default and common on many modern boards. Other supported rates: 9600, 19200, 38400, 57600, and 230400.

The baud rate must match what your firmware calls in Serial.begin(...) (or equivalent) or you will see garbled output.

4. Connect

Click Connect. On success you will see:

[connected] /dev/ttyUSB0 @ 115200

Live device output streams into the panel immediately. Connect is disabled while connected; use Disconnect to release the port.

Reading output

Long sessions are trimmed automatically so the panel stays responsive.

Sending data to the device

1. Ensure you are connected.
2. Type in Send data to device... and click Send, or press Enter.
3. Choose a line ending if your firmware expects one:
   • No line ending — raw payload only
   • LF (\n) — common on Unix-style firmware
   • CRLF (\r\n) — common on some AT-command modules
   • CR (\r) — legacy serial devices

Sent traffic is logged in the output as [tx] (text) or [tx hex] (hex mode).

HEX send mode

Enable HEX send to transmit raw bytes. Enter an even number of hex characters, with or without spaces:

48 65 6c 6c 6f

This sends the bytes for Hello. Invalid or odd-length hex input is rejected with a status message.

Suggested workflow with ACE

1. Edit firmware in the Monaco editor (for example firmware/IoT_handler.cpp).
2. Build and flash using the Terminal tab or Run Task....
3. Connect IoT Monitor and watch boot logs and sensor readings.
4. Send test commands or configuration strings to the device.
5. Filter or enable HEX view when debugging binary protocols.
6. Enable Share with AI and click AI Debug to let ACE analyze serial output against your firmware.

Only one ACE window can hold an active serial connection at a time.

ACE AI integration (Autonomous Hardware Debugger)

When Share with AI is enabled (default), ACE attaches the last 200 lines of serial output to AI Agent requests while the IoT Monitor is connected. The Electron main process maintains a rolling serial log buffer so the AI sees live USB data—not only what is visible on screen.

Example prompts:

• "Why is my ESP32 rebooting in a loop?"
• "Parse this sensor telemetry and find the bad reading"
• "Device prints Guru Meditation Error — fix the firmware"

Hardware-debug prompts route to Gemini Pro for deeper reasoning.

Autonomous serial probes

When Share with AI is on and IoT Monitor is connected, the ACE Agent can call send_serial_command (with your approval) to:

1. Send a test string or AT command to the device
2. Wait for a response (default 1 second)
3. Read new serial output and continue debugging in a loop

Example agent flow: analyze panic log → send AT+CSQ? → read response → patch firmware.

Auto-approve read-only queries

Enable Auto-approve read-only (default on) in IoT Monitor to skip confirmation for safe probes:

Blocked commands are never sent (even if approved). Use Remember on a read-only prompt to auto-approve when the checkbox is off.

Server IoT context API

The desktop IDE syncs the rolling buffer to Laravel (10-minute cache):

If a chat request omits iot_serial_monitor, the backend merges the cached snapshot automatically.

Log line highlighting

When ACE cites a timestamp or quoted log fragment in its reply, matching lines in IoT Monitor pulse yellow for ~12 seconds.

Troubleshooting

Port busy

Another application (Arduino IDE Serial Monitor, screen, minicom, PlatformIO monitor, etc.) may already have the port open.

• Close the other tool, then click Reconnect in the banner or Connect again.
• Or pick a different port if multiple interfaces are listed.

Permission denied (Linux)

Your user may not have access to /dev/ttyUSB* or /dev/ttyACM*.

• Add your user to the dialout group (or equivalent for your distribution), then log out and back in.
• Check udev rules for custom USB VID/PID devices.

Device disconnected

The cable was unplugged, the board reset, or the port vanished.

• Re-seat USB, wait for the device to re-enumerate, click Refresh, select the port, and Connect (or Reconnect).

Garbled characters

• Baud rate mismatch — try the rate configured in firmware.
• Wrong line ending when sending — match what the device parser expects.

Serial monitor unavailable

If ACE reports that the serial module is not loaded, use a desktop build that includes the serialport dependency, or reinstall from the latest ACE release.

IoT monitor visuals

Quick reference