The Texas Instruments MSP430 family of ultra-low-power microcontrollers consists of several devices featuring different sets of peripherals targeted for various applications. The architecture, combined with five low-power modes, is optimized to achieve extended battery life in portable measurement applications. The device features a powerful 16-bit RISC CPU, 16-bit registers, and constant generators that contribute to maximum code efficiency. The digitally controlled oscillator (DCO) allows wake-up from low-power modes to active mode in less than 1 µs. The MSP430F21x2 series is an ultra-low-power microcontroller with two built-in 16-bit timers, a fast 10-bit A/D converter with integrated reference and a data transfer controller (DTC), a comparator, built-in communication capability using the universal serial communication interface, and up to 24 I/O pins.