void DMAInit(void)
{
DMA_disableTransferDuringReadModifyWrite();
DMA_initParam initParam = {0};
initParam.channelSelect = DMA_CHANNEL_0;
initParam.transferModeSelect = DMA_TRANSFER_REPEATED_BLOCK;
initParam.transferSize = 3;
initParam.triggerSourceSelect = DMA_TRIGGERSOURCE_24;
initParam.transferUnitSelect = DMA_SIZE_SRCWORD_DSTWORD;
initParam.triggerTypeSelect = DMA_TRIGGER_RISINGEDGE;
DMA_init(&initParam);
DMA_setSrcAddress(DMA_CHANNEL_0,
ADC12_A_getMemoryAddressForDMA(ADC12_A_BASE,
ADC12_A_MEMORY_0),
DMA_DIRECTION_INCREMENT);
DMA_setDstAddress(DMA_CHANNEL_0,
(uint32_t)&DMA_DST,
DMA_DIRECTION_INCREMENT);
//Enable DMA channel 0 interrupt
DMA_clearInterrupt(DMA_CHANNEL_0);
DMA_enableInterrupt(DMA_CHANNEL_0);
//Enable transfers on DMA channel 0
DMA_enableTransfers(DMA_CHANNEL_0);
}
void main (void)
{
unsigned int ADC_Result[64];
volatile unsigned int ADC_Result_Average;
unsigned char i;
unsigned int ADC_Result_sum;
//Stop Watchdog Timer
WDT_hold(__MSP430_BASEADDRESS_WDT_A__);
//Initialize the ADC10 Module
/*
* Base Address for the ADC10 Module
* Use internal ADC10 bit as sample/hold signal to start conversion
* USE MODOSC 5MHZ Digital Oscillator as clock source
* Use default clock divider of 1
*/
ADC10_init(__MSP430_BASEADDRESS_ADC10_A__,
ADC10_SAMPLEHOLDSOURCE_SC,
ADC10_CLOCKSOURCE_ADC10OSC,
ADC10_CLOCKDIVIDER_1);
ADC10_enable(__MSP430_BASEADDRESS_ADC10_A__);
/*
* Base Address for the ADC10 Module
* Sample/hold for 16 clock cycles
* Enable Multiple Sampling
*/
ADC10_setupSamplingTimer(__MSP430_BASEADDRESS_ADC10_A__,
ADC10_CYCLEHOLD_16_CYCLES,
ADC10_MULTIPLESAMPLESENABLE);
//Configure Memory Buffer
/*
* Base Address for the ADC10 Module
* Use input A1
* Use positive reference of AVcc
* Use negative reference of AVss
*/
ADC10_memoryConfigure(__MSP430_BASEADDRESS_ADC10_A__,
ADC10_INPUT_A1,
ADC10_VREFPOS_AVCC,
ADC10_VREFNEG_AVSS);
//Initialize and Setup DMA Channel 0
/*
* Base Address for the DMA Module
* Configure DMA channel 0
* Configure channel for repeated single transfer
* DMA interrupt flag will be set after every 64 transfers
* Use DMA Trigger Source 24 (ADC10IFG)
* Transfer Word-to-Word
* Trigger upon Rising Edge of Trigger Source Signal
*/
DMA_init(__MSP430_BASEADDRESS_DMAX_3__,
DMA_CHANNEL_0,
DMA_TRANSFER_REPEATED_SINGLE,
64,
DMA_TRIGGERSOURCE_24,
DMA_SIZE_SRCWORD_DSTWORD,
DMA_TRIGGER_RISINGEDGE);
/*
* Base Address for the DMA Module
* Configure DMA channel 0
* Use ADC10 Memory Buffer as source
* Increment destination address after every transfer
*/
DMA_setSrcAddress(__MSP430_BASEADDRESS_DMAX_3__,
DMA_CHANNEL_0,
ADC10_getMemoryAddressForDMA(__MSP430_BASEADDRESS_ADC10_A__),
DMA_DIRECTION_UNCHANGED);
/*
* Base Address for the DMA Module
* Configure DMA channel 0
* Use ADC_Result[0] as destination
* Increment destination address after every transfer
*/
DMA_setDstAddress(__MSP430_BASEADDRESS_DMAX_3__,
DMA_CHANNEL_0,
(unsigned long)&ADC_Result[0],
DMA_DIRECTION_INCREMENT);
//Enable DMA channel 0 interrupt
DMA_enableInterrupt(__MSP430_BASEADDRESS_DMAX_3__,
DMA_CHANNEL_0);
//Enable transfers on DMA channel 0
DMA_enableTransfers(__MSP430_BASEADDRESS_DMAX_3__,
DMA_CHANNEL_0);
while (1)
{
//Enable and Start the conversion
//in Repeated Single-Channel Conversion Mode
ADC10_startConversion(__MSP430_BASEADDRESS_ADC10_A__,
ADC10_REPEATED_SINGLECHANNEL);
__bis_SR_register(CPUOFF + GIE); //LPM0, ADC10_ISR will force exit
__no_operation(); //For debug only
//Clear accumulate register
ADC_Result_sum = 0x0;
for (i = 0; i < 64; i++){
ADC_Result_sum += ADC_Result[i];
}
//Average of 64 conversions results
ADC_Result_Average = ADC_Result_sum >> 6;
//SET BREAKPOINT HERE to be able to watch ADC_Result_Average
//Delay before next 64 conversions
__delay_cycles(50000);
}
}