Development Setup

The RoArm-M2-S runs on an ESP32 MCU. To modify or reflash the firmware, you need Arduino IDE configured with the ESP32 board support package.

Prerequisites

• Arduino IDE 2.x (or 1.8.x)
• USB-C cable
• CP2102 or CH340 USB-serial driver (usually included with your OS)

Arduino IDE Setup

1. Install Arduino IDE from arduino.cc

2. Add ESP32 board support

   Open File → Preferences and add this URL to “Additional boards manager URLs”:

   https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

3. Install the ESP32 package

   Go to Tools → Board → Boards Manager, search for “esp32”, and install esp32 by Espressif Systems (version 2.x recommended).

4. Select the board

   Tools → Board → ESP32 Arduino → ESP32 Dev Module

5. Configure upload settings

   Setting	Value
   Board	ESP32 Dev Module
   Upload Speed	921600
   Flash Frequency	80MHz
   Flash Size	4MB (32Mb)
   Partition Scheme	Default 4MB with spiffs
   Port	(your USB-serial port)

Required Libraries

Install these through Sketch → Include Library → Manage Libraries:

Library	Purpose
ArduinoJson	JSON command parsing
ESP32Servo	Servo PWM control
SCServo	Serial bus servo protocol
ESPAsyncWebServer	HTTP server for web control
AsyncTCP	Async TCP for the web server
SPIFFS	Flash file system (built-in)

Tip

The firmware source code is available from Waveshare’s GitHub. Clone the repository to get all example sketches and the complete firmware.

Firmware Structure

The main firmware sketch is organized around the JSON command dispatcher in json_cmd.h. Each command type (T code) maps to a handler function:

RoArm-M2_example/
├── RoArm-M2_example.ino    # Main sketch, setup/loop
├── json_cmd.h               # Command type definitions
├── ctrl.h                   # Motion control & kinematics
├── wifi_ctrl.h              # WiFi AP/STA configuration
├── esp_now_ctrl.h           # ESP-NOW peer-to-peer
├── file_ctrl.h              # SPIFFS file operations
└── mission_ctrl.h           # Step recording & playback

Flashing Firmware

1. Connect the ESP32 board via USB-C

2. Select the correct port in Tools → Port

3. Hold the BOOT button on the ESP32 board, click Upload in Arduino IDE, then release BOOT when you see “Connecting…”

4. Wait for upload to complete. The serial monitor (115200 baud) will show startup messages.

Caution

After flashing, the ESP32 reboots and starts the WiFi access point. Your existing WiFi configuration stored in NVS will persist across firmware updates. If WiFi behaves unexpectedly after a flash, clear NVS with {"T":604}.

Verifying the Flash

Open the Serial Monitor at 115200 baud. You should see boot messages and the WiFi configuration. Send a test command:

{"T":105}

This requests position feedback. A working arm will respond with current joint positions and XYZ coordinates.

Alternative: PlatformIO

If you prefer PlatformIO over Arduino IDE, create a platformio.ini:

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
upload_speed = 921600
lib_deps =
    bblanchon/ArduinoJson
    madhephaestus/ESP32Servo
    ESPAsyncWebServer
    AsyncTCP

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Development workflow based on the Waveshare Secondary Development Tool guide. Firmware: waveshareteam/roarm_m2.