Gumstix are computer motherboards that are 3.1 x 0.8 x 0.3 inches (20 x 80 x 8mm), and are suppose to weigh "less than a tablespoon of water," according to Gumstix. They're powered by XScale (ARM-based) Intel PXA255 SoC (System-on-Chip) running at 200MHz or 400MHz. They include 64 MB of SDRAM, 4 MB of Flash, and a complement of peripherals and I/O that includes an LCD controller, two RS232 serial ports, a USB 1.1 device port, I2C, two NSSP PWMs, AC97, and a JTAG port.
These are very impressive little computers. They run a Linux OS, and are designed for specialized applications. For example they can be used for controlling different types of robotics.
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