We have many tiny and compact Arm Linux SBC on the market today, ranging from NanoPi NEO to Raspberry Pi Zero or Rock Pi S. However, Daniel Palmer is launching a crowdfunding campaign for the BreadBee, which is tiny, but yet fully-functional Linux-based single-board computer designed based on MStar MSC313E Cortex-A7 system-on-chip (SoC) originally aimed at IP cameras. Palmer say:
The BreadBee is based on a relatively unknown IP camera SoC, the MSC313E, from a company called MStar.” He continues “You might have never heard of MStar but you probably have one of their chips in your TV. There are no solutions yet that can run a real OS like Linux that can be integrated by hobbyists into boards from cheap PCB vendors that don’t have show stopping limitations; i.e. the AllWinner V3s is very similar to the SoC used here but it only has one SPI controller that is lost as soon as you put SPI NOR on it… The MSC313E has just enough of the usual microcontroller peripherals to make it useful, comes in a (relatively) easy to work with QFN package, is tiny and costs ~$4. It is a bit harder to integrate into your designs than a microcontroller that requires a single power supply but all of the information you would need to do so is right here. The schematic for the BreadBee is incredibly simple.
At 32x30mm (around 1.26×1.18″) in footprint, which is smaller than any Arm Linux SBC on the market today, the compact BreadBee features a wide range of specifications. It includes a single-core 1GHz Arm Cortex-A7 with NEON instructions, 64MB of DDR2 memory, 64kB of static RAM, bootable and memory-mapped SPI-NOR, a 100Mb Ethernet port. It also includes 24-pin dual-row header (2.54mm pitch) with SPI, I2C, 4x 10-bit ADC, 3x UART, GPIOs 21-pin header (1.27mm pitch) with SD/SDIO, USB 2.0, GPIOs, eight pulse-width modulated (PWM) pins, a real-time clock, watchdog timer, SD/SDIO interface, a USB PHY and host/device mux. The networking feature includes 10/100M Ethernet (RJ45).