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//******************************************************************************
// MSP430F5438 Demo - ADC12, Sequence of Conversions (non-repeated)
//
// Description: This example shows how to perform A/D conversions on a sequence
// of channels. A single sequence of conversions is performed - one conversion
// each on channels A0, A1, A2, and A3. Each conversion uses AVcc and AVss for
// the references. The conversion results are stored in ADC12MEM0, ADC12MEM1,
// ADC12MEM2, and ADC12MEM3 respectively and are moved to 'results[]' upon
// completion of the sequence. Test by applying voltages to pins A0, A1, A2,
// and A3, then setting and running to a break point at the "_BIC..."
// instruction in the ISR. To view the conversion results, open a watch window
// in debugger and view 'results' or view ADC12MEM0, ADC12MEM1, ADC12MEM2, and
// ADC12MEM3 in an ADC12 SFR window.
// This can run even in LPM4 mode as ADC has its own clock
// 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 MSP430x5xx User's Guide for instructions on using the ADC12.
//
// MSP430F5438
// -----------------
// /|\| |
// | | |
// --|RST |
// | |
// Vin0 -->|P6.0/A0 |
// Vin1 -->|P6.1/A1 |
// Vin2 -->|P6.2/A2 |
// Vin3 -->|P6.3/A3 |
// | |
//
// M Smertneck / W. Goh
// Texas Instruments Inc.
// September 2008
// Built with CCE Version: 3.2.2 and IAR Embedded Workbench Version: 4.11B
//******************************************************************************
#include "msp430x54x.h"
volatile unsigned int results[4]; // Needs to be global in this example
// Otherwise, the compiler removes it
// because it is not used for anything.
void main(void)
{
WDTCTL = WDTPW+WDTHOLD; // Stop watchdog timer
P6SEL = 0x0F; // Enable A/D channel inputs
ADC12CTL0 = ADC12ON+ADC12MSC+ADC12SHT0_2; // Turn on ADC12, set sampling time
ADC12CTL1 = ADC12SHP+ADC12CONSEQ_1; // Use sampling timer, single sequence
ADC12MCTL0 = ADC12INCH_0; // ref+=AVcc, channel = A0
ADC12MCTL1 = ADC12INCH_1; // ref+=AVcc, channel = A1
ADC12MCTL2 = ADC12INCH_2; // ref+=AVcc, channel = A2
ADC12MCTL3 = ADC12INCH_3+ADC12EOS; // ref+=AVcc, channel = A3, end seq.
ADC12IE = 0x08; // Enable ADC12IFG.3
ADC12CTL0 |= ADC12ENC; // Enable conversions
while(1)
{
ADC12CTL0 |= ADC12SC; // Start convn - software trigger
__bis_SR_register(LPM4_bits + GIE); // Enter LPM4, Enable interrupts
__no_operation(); // For debugger
}
}
#pragma vector=ADC12_VECTOR
__interrupt void ADC12ISR (void)
{
switch(__even_in_range(ADC12IV,34))
{
case 0: break; // Vector 0: No interrupt
case 2: break; // Vector 2: ADC overflow
case 4: break; // Vector 4: ADC timing overflow
case 6: break; // Vector 6: ADC12IFG0
case 8: break; // Vector 8: ADC12IFG1
case 10: break; // Vector 10: ADC12IFG2
case 12: // Vector 12: ADC12IFG3
results[0] = ADC12MEM0; // Move results, IFG is cleared
results[1] = ADC12MEM1; // Move results, IFG is cleared
results[2] = ADC12MEM2; // Move results, IFG is cleared
results[3] = ADC12MEM3; // Move results, IFG is cleared
__bic_SR_register_on_exit(LPM4_bits); // Exit active CPU, SET BREAKPOINT HERE
case 14: break; // Vector 14: ADC12IFG4
case 16: break; // Vector 16: ADC12IFG5
case 18: break; // Vector 18: ADC12IFG6
case 20: break; // Vector 20: ADC12IFG7
case 22: break; // Vector 22: ADC12IFG8
case 24: break; // Vector 24: ADC12IFG9
case 26: break; // Vector 26: ADC12IFG10
case 28: break; // Vector 28: ADC12IFG11
case 30: break; // Vector 30: ADC12IFG12
case 32: break; // Vector 32: ADC12IFG13
case 34: break; // Vector 34: ADC12IFG14
default: break;
}
}
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