Hi, Anyone used I2C on Xiao MG24? The same simple sketch worked on XIAO NRF version but unfortunately failed on MG24. Are there any known bugs in XIAO MG? I am using Arduino platform.

Hi there, So Check this thread, there were some early issues but AFAIK it’s all sorted now. [image] Xiao MG24 Sense onboard gyroscope XIAO Hi there, As Luck would have it , Seeed Engineers @Chunchun put up an updated LIB for it and Updated the Wiki page too, I can confir…

[image] Wojtek_B: Hi, Anyone used I2C on Xiao MG24? The same simple sketch worked on XIAO NRF version but unfortunately failed on MG24. Are there any known bugs in XIAO MG? I am using Arduino platform. For boards like the XIAO MG24 Sense, the onboard IMU might require enabling a specific GPIO…

Most of examples uses Xiao in I2C master mode. I use it an I2C slave and it simply does not work. The same code and setup for NRF works.

[image] Wojtek_B: The same simple sketch worked on XIAO NRF version but unfortunately failed on MG24 Submit your sketches. I have both the nRF52 and MG24 on hand so I can try them out.

Master code running on ESP32: Serial.println("Initializing I2C..."); Wire.begin(I2C_SDA, I2C_SCL); Wire.setClock(400000); // Set I2C clock speed to 100kHz //delay(3000); // Give time to boot Serial.println("Scanning I2C bus..."); for (uint8_t addr = 1; addr < 127; addr++) …

The master is ESP32, correct? Have you ever run it on a non-ESP32 board? For example ESP32C3_XIAO. Please post the entire sketchs. How many ohms is the pull-up resistors?

Master is ESP 32 S3 board (not Xiao), 4.7k pullup resistors. Slave MG24 code: #include <Wire.h> #define I2C_ADDRESS 0x42 uint8_t buffer[12]; // Dummy 12-byte data void onRequestHandler() { Wire.write(buffer, sizeof(buffer)); Serial.println("buffer sent"); } void setup() { Serial.begin(1…

I have tried with the MG24 and nRF52 using the ESP32S3_XIAO as the master. No problem with nRF52, but MG24 does not detect 0x42 as you say. When I connect the SCL of MG24, the SCL of S3 goes LOW and I2C stops working. The cause is under investigation. EDIT: The MG24 is returning ACK to all calls…

With MG24 as a Leader (aka master) try this… for (address = 1; address < 127; address++) { Wire.beginTransmission(address); Wire.write(0xFF); //Send 1 dummy byte i2c_error = Wire.endTransmission(); if (i2c_error == 0) { Serial.print("I2C device found at 0x"); Serial.p…

Neither SCL nor SDA will change. Do you know why NACK is not output except 0x42?

XIAO MG24 I2C support

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PJ_Glasso May 11, 2025, 9:46pm 2

Hi there,

So Check this thread, there were some early issues but AFAIK it’s all sorted now.

HTH
GL PJ