MSP430X149的模数转换例程，详细内容请见英文说明-MSP430 ADC Demo: A single sample is made on A0 with reference to AVcc. Software sets ADC10SC to start sample and conversion- ADC12SC automatically cleared at EOC. ADC12 internal oscillator times sample (16x) and conversion. In Mainloop MSP430 waits in LPM0 to save power until ADC12 conversion complete, ADC12_ISR will force exit from LPM0 in Mainloop on reti. If A0 > 0.5*AVcc, P1.0 set, else reset.