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问 我想用AD12进行数据采集，利用多通道多次转换，但是不知道采样频率怎么设置，哪位大侠帮帮忙了。谢谢了 答 1: ADC12CTL0的SHT0和SHT1是设置采样频率的。你可以参考下面程序：
//******************************************************************************
// MSP-FET430P140 Demo - ADC12, Repeated Sequence of Conversions
//
// This example shows how to perform a repeated sequence of conversions using
// "repeat sequence-of-channels" mode. AVcc is used for the reference and
// repeated sequence of conversions is performed on Channels A0, A1, A2, and
// A3. Each conversion result is stored in ADC12MEM0, ADC12MEM1, ADC12MEM2,
// and ADC12MEM3 respectively. After each sequence, the 4 conversion results
// are moved to A0results[], A1results[], A2results[], and A3results[]. Test
// by applying voltages to channels A0 - A3. Open a watch window in C-Spy and
// view the results. Set a breakpoint in the last line to see the array values
// change sequentially.
//
// Note that a sequence has no restrictions on which channels are converted.
// For example, a valid sequence could be A0, A3, A2, A4, A2, A1, A0, and A7.
// See the MSP430x1xx User's Guide for instructions on using the ADC12.
//
//
// MSP430F149
// -----------------
// | |
// | A0 |<---- Vin0
// | A1 |<---- Vin1
// | A2 |<---- Vin2
// | A3 |<---- Vin3
// | |
//
//
// M.Mitchell
// Texas Instruments, Inc
// January, 2002
// Built with IAR Embedded Workbench Version: 1.25A
// December 2003
// Updated for IAR Embedded Workbench Version: 2.21B
//******************************************************************************

#include "MSP430x14x.h" // Standard Equations

#define Num_of_Results 8

static unsigned int A0results[Num_of_Results]; // These need to be global in
static unsigned int A1results[Num_of_Results]; // this example. Otherwise, the
static unsigned int A2results[Num_of_Results]; // compiler removes them because
static unsigned int A3results[Num_of_Results]; // they are not used

void main(void)
{
WDTCTL = WDTPW+WDTHOLD; // Stop watchdog timer
P6SEL = 0x0F; // Enable A/D channel inputs
ADC12CTL0 = ADC12ON+MSC+SHT0_8; // Turn on ADC12, extend sampling time
// to avoid overflow of results
ADC12CTL1 = SHP+CONSEQ_3; // Use sampling timer, repeated sequence
ADC12MCTL0 = INCH_0; // ref+=AVcc, channel = A0
ADC12MCTL1 = INCH_1; // ref+=AVcc, channel = A1
ADC12MCTL2 = INCH_2; // ref+=AVcc, channel = A2
ADC12MCTL3 = INCH_3+EOS; // ref+=AVcc, channel = A3, end seq.
ADC12IE = 0x08; // Enable ADC12IFG.3
ADC12CTL0 |= ENC; // Enable conversions
_EINT(); // Enable interrupts
ADC12CTL0 |= ADC12SC; // Start conversion
_BIS_SR(LPM0_bits); // Enter and stay in LPM0
}

#pragma vector=ADC_VECTOR
__interrupt void ADC12ISR (void)
{
static unsigned int index = 0;

A0results[index] = ADC12MEM0; // Move A0 results, IFG is cleared
A1results[index] = ADC12MEM1; // Move A1 results, IFG is cleared
A2results[index] = ADC12MEM2; // Move A2 results, IFG is cleared
A3results[index] = ADC12MEM3; // Move A3 results, IFG is cleared
index = (index+1)%Num_of_Results; // Increment results index, modulo; Set Breakpoint here
} 答 2: 版主大人，你还没有具体告诉我这个程序怎么个解释啊，ADC12CTL0 = ADC12ON+MSC+SHT0_8; // Turn on ADC12, extend sampling time。这句有告诉我频率是多少吗？
我真的很笨，但我愿意学，你不要生气吗！ 答 3: 采样时间由SHT0_8确定
T=4*ADC12CLK周期*8 答 4: 谢谢了！时钟是系统时钟吧！