MSP430F169 AD采样参考电压设置问题

只看该作者 · 2013-5-31 20:39

请问我怎么样才能MSP430F169的AD采样参考电压设置为1.5V，我在程序中这样写:
P6SEL |= 0x20;
ADC12CTL0 = ADC12ON + SHT0_15 + MSC;    // Turn on ADC12, set sampling time
ADC12CTL0 |= REFON;
ADC12CTL1 = SHP + CONSEQ_2;             // Use sampling timer, set mode
ADC12MCTL0 |= 0x05;
ADC12IE = 0x01;                         // Enable ADC12IFG.0
ADC12CTL0 |= ENC;                      // Enable conversions
ADC12CTL0 |= ADC12SC;                   // Start conversion

DAC12_0CTL = DAC12IR + DAC12AMP_5 + DAC12ENC;
结果DA的参考电压是1.5V，但是AD的参考电压还是3.3V，请问我哪个寄存器配置错了？