STMicroelectronics STEVAL-MKI121V1

Overview

STEVAL-MKI121V1 from STMicroelectronics is an evaluation board (Discovery-M1) designed to interface with the iNEMO SDK for sensor fusion development, featuring an STM32F103 microcontroller, on-board 6-axis inertial module (LSM303DLHC), pressure sensor (LPS331AP), and temperature sensor (STLM75). It supports USB Virtual COM communication, firmware update via DFU mode, and real-time sensor parameter configuration including accelerometer full-scale (±2/±4/±8/±16 g), gyroscope output data rate (up to 1.6 kHz), and magnetometer operating modes.

For engineers reviewing the STEVAL-MKI121V1 datasheet, STEVAL-MKI121V1 pinout, STEVAL-MKI121V1 application, or STEVAL-MKI121V1 equivalent, this board enables rapid validation of AHRS algorithms, sensor calibration workflows, USB-based host-to-sensor command framing (CONTROL/DATA/ACK/NACK), and embedded firmware version interrogation (Get_FW_Version, Get_HW_Version) in industrial motion sensing and navigation prototyping.

Technical Context

The STEVAL-MKI121V1 implements a deterministic, message-oriented communication protocol over USB Virtual COM, using fixed 3-byte headers (Frame Control, Length, Message ID) and optional up to 61-byte payloads. Frame types include CONTROL (e.g., iNEMO_Connect, iNEMO_Reset), DATA (e.g., iNEMO_Get_Acquired_Data), ACK, and NACK - each with defined QoS priority (Normal/Medium/High) and fragmentation support (LF/MF bit).

It hosts an STM32F103C8T6 MCU running firmware that exposes sensor control via structured frames: iNEMO_Set_Sensor_Parameter configures accelerometer high-pass filter cutoff or gyroscope scale factor; iNEMO_Start_Acquisition initiates streaming of fused orientation data; iNEMO_Get_Available_Sensors returns enumerated sensor list (accelerometer, gyroscope, magnetometer, pressure, temperature) with hardware-validated presence.

Key Specifications

Availability

STEVAL-MKI121V1 is available at Aetrix Electronics and suitable for industrial motion sensing validation, AHRS algorithm development, and sensor fusion firmware testing requiring stable component supply and documented SDK interoperability.

Supply support for STEVAL-MKI121V1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in microcontrollers, sensors, power management, and analog ICs for industrial, automotive, and consumer applications.

This board belongs to ST's iNEMO ecosystem - a family of motion-sensing evaluation platforms built around STM32 MCUs and MEMS sensors, designed specifically to accelerate development of orientation-aware applications like robotics stabilization, wearable gesture recognition, and drone navigation.

FAQ

What software tools are required to use the STEVAL-MKI121V1?

The board requires the iNEMO SDK (Software Development Kit), which provides the PC-side GUI, firmware libraries, and API documentation. The SDK supports Windows and includes prebuilt binaries for sensor data visualization, AHRS output display, and command-line frame injection. No additional IDE or compiler is needed for basic operation, though source code access allows customization of the embedded firmware.

Does the STEVAL-MKI121V1 support firmware updates in the field?

Yes - it supports Device Firmware Upgrade (DFU) mode via the iNEMO_Enter_DFU_Mode command, which triggers a software reset into USB DFU bootloader state. Once in DFU mode, new firmware can be loaded using DfuSe Demo or compatible tools. The board retains its unique device ID and hardware version across updates, ensuring traceability in development environments.

Can the STEVAL-MKI121V1 operate without a PC host?

No - it is a USB-dependent evaluation board with no standalone operation capability. All sensor acquisition, configuration, and data streaming require active communication with the iNEMO SDK or custom host application over the Virtual COM port. There is no onboard storage, battery, or wireless interface; it draws power exclusively from the USB bus.

How is sensor calibration performed on this board?

Calibration is executed via the iNEMO_Start_HIC (Hard Iron Calibration) frame, which initiates a multi-step magnetic sensor calibration routine. The board responds with status frames during calibration, and results are stored in flash using iNEMO_Save_to_Flash. Accelerometer and gyroscope offsets/scale factors can also be adjusted individually via iNEMO_Set_Sensor_Parameter before saving.