Mbed online development system (wiki)
Freescale product summary

Cortex-M0+ (wiki)
MKL25Z128VLK4 datasheet (PDF)

Cortex-M0+ r0p0 Technical Reference Manual; ARM Holdings (PDF)
The processor is a Freescale MKL25Z128VLK4, which is a implementation of a Cortex-M0+ core, which a low-power CPU using the ARMv6-M Thumb instruction set.core. Features:
Pinout:
block diagram
pinout PDF
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