U21B4

U21B4 is a fictional designation used in this article to illustrate a compact, modular single-board computer designed for education and prototyping. It is attributed here to a hypothetical company, Nebula Labs, and is discussed as a reference model in open-source hardware communities.

The U21B4 is imagined as a credit-card–sized board featuring a 64-bit quad-core processor, an integrated graphics subsystem, and RAM configurations of 2 GB or 4 GB. It provides expandability through microSD storage, a PCIe-like slot, and common I/O such as HDMI, USB, and Ethernet. The design emphasizes low power consumption and straightforward assembly for classroom and hobbyist use.

Connectivity options include optional 802.11ac Wi‑Fi and Bluetooth, plus wired Gigabit Ethernet. Power is supplied via USB-C, intended for safe operation in educational settings and makerspaces. An open-source reference design and schematics are published to support hardware hacking, modification, and hands-on learning.

Software support centers on a Linux-based operating system with package availability for Python, Node.js, and other development tools. The platform is marketed for beginner-friendly robotics, media projects, and edge computing experiments, with an emphasis on accessible documentation and community-driven tutorials.

Variants named U21B4-A and U21B4-B differentiate RAM and storage options, offering practical choices for schools and clubs. In the fictional ecosystem, the model generated interest for low-cost experimentation and rapid prototyping, positioning it as a teaching tool and starter platform in imagined open-source hardware programs. See also: Raspberry Pi, Arduino.