Dual Screens, Triple Cores: The Ultimate IoT Board

For most electronics hobbyists, keeping a few all-in-one development boards on hand is considered essential for quickly bringing new ideas to life. These compact devices usually combine a microcontroller, a display, and various communication interfaces into a single, easy-to-use platform. While they’re certainly convenient, they often fall short when it comes to raw processing power and sensing capabilities. These limitations make them well-suited for simple builds, but less ideal for tackling more advanced or demanding projects.

ElecLab has created an unusual DIY IoT development platform that is meant to overcome these limitations. It is equipped with three powerful processing cores, plenty of memory and storage, lots of sensing options, and dual 2.16-inch displays. With so much already included onboard, many projects can be built without adding any hardware beyond what is already available.

At the core of the system is the BK7258, a low-power IoT chip built around an Arm Cortex-M33 architecture. It features a tri-core configuration consisting of one core running at 240 MHz and two cores at 480 MHz, paired with 8 MB of flash and 16 MB of PSRAM. Despite this performance, the platform remains relatively efficient and is capable of running graphical interfaces with surprisingly low current draw. The board leverages LVGL for its interface, with careful optimization required to adapt between different library versions during development.

Each 480×480 screen serves a distinct purpose: one is dedicated to GPS mapping, while the other presents motion data and system information. Together, they form a combined 480×960 interface, giving the device a smartwatch-like layout but with significantly more flexibility. The displays can be controlled independently, allowing one screen to power down when not in use to conserve energy.

Beyond processing and display capabilities, the platform also includes a wide array of sensors and communication modules. It includes multi-band GNSS support (covering GPS, GLONASS, Galileo, and others), a global 4G module, and environmental sensors for motion, orientation, pressure, and temperature. A compact camera module, microphone, and speaker further expand its potential use cases, enabling everything from wearable assistants to data logging and imaging applications.

To keep the device small, a compact four-layer PCB was populated with extremely small components, including 0201 capacitors and a tiny camera sensor package. Powered by a rechargeable lithium battery, the entire system is housed in a 3D-printed enclosure with a wearable form factor.

For more details on the build, be sure to check out the full project write-up.