Mischa Megens / DMAFuncGen

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Dependents:   DACDMAfuncgenlib

DMAFuncGen.cpp@0:337ad0fe7734, 2013-12-29 (annotated)

Committer:
Mischa
Date:
Sun Dec 29 01:00:30 2013 +0000
Revision:
0:337ad0fe7734
First version.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Mischa 0:337ad0fe7734 1 #include "assert.h"
Mischa 0:337ad0fe7734 2 #include "DMAFuncGen.h"
Mischa 0:337ad0fe7734 3
Mischa 0:337ad0fe7734 4 //DigitalOut led1(LED1);
Mischa 0:337ad0fe7734 5
Mischa 0:337ad0fe7734 6 DMAFuncGen::DMAFuncGen(MODDMA& dma, MODDMA::CHANNELS channel) : dma(dma) {
Mischa 0:337ad0fe7734 7 conf.channelNum( channel );
Mischa 0:337ad0fe7734 8 buffer_size = 0;
Mischa 0:337ad0fe7734 9 buffer = NULL;
Mischa 0:337ad0fe7734 10 }
Mischa 0:337ad0fe7734 11
Mischa 0:337ad0fe7734 12 #define DAC_POWER_MODE (0 << 16) // DAC output power mode.
Mischa 0:337ad0fe7734 13
Mischa 0:337ad0fe7734 14 uint16_t DMAFuncGen::operator[](const uint16_t idx) {
Mischa 0:337ad0fe7734 15 assert(buffer!=NULL);
Mischa 0:337ad0fe7734 16 assert(idx<buffer_size);
Mischa 0:337ad0fe7734 17 return buffer[idx] & 0xFFC0;
Mischa 0:337ad0fe7734 18 }
Mischa 0:337ad0fe7734 19
Mischa 0:337ad0fe7734 20 void DMAFuncGen::set(int idx, uint16_t x) {
Mischa 0:337ad0fe7734 21 // V = (x>>6) × ((VrefP - VrefN)/1024) + VrefN; VrefN = 0V; VrefP = 3.3V;
Mischa 0:337ad0fe7734 22 buffer[idx] = DAC_POWER_MODE | (x & 0xFFC0);
Mischa 0:337ad0fe7734 23 }
Mischa 0:337ad0fe7734 24
Mischa 0:337ad0fe7734 25 void DMAFuncGen::Connect() {
Mischa 0:337ad0fe7734 26 // Connect DAC to pin
Mischa 0:337ad0fe7734 27 LPC_PINCON->PINSEL1 &= ~(3UL <<20);
Mischa 0:337ad0fe7734 28 LPC_PINCON->PINSEL1 |= 2UL <<20; //AOUT
Mischa 0:337ad0fe7734 29 LPC_PINCON->PINMODE1 &= ~(3UL <<20);
Mischa 0:337ad0fe7734 30 LPC_PINCON->PINMODE1 |= (2UL <<20); // neither pull-up nor pull-down
Mischa 0:337ad0fe7734 31 LPC_PINCON->PINMODE_OD0 &= ~(1UL <<26); // normal (not open drain) mode
Mischa 0:337ad0fe7734 32 }
Mischa 0:337ad0fe7734 33
Mischa 0:337ad0fe7734 34 void DMAFuncGen::Disconnect() {
Mischa 0:337ad0fe7734 35 LPC_PINCON->PINSEL1 &= ~(3UL <<20);
Mischa 0:337ad0fe7734 36 LPC_PINCON->PINSEL1 |= 1UL <<20; //AD0.3, input
Mischa 0:337ad0fe7734 37 LPC_PINCON->PINMODE1 &= ~(3UL <<20);
Mischa 0:337ad0fe7734 38 LPC_PINCON->PINMODE1 |= (2UL <<20); // neither pull-up nor pull-down
Mischa 0:337ad0fe7734 39 LPC_PINCON->PINMODE_OD0 &= ~(1UL <<26); // normal (not open drain) mode
Mischa 0:337ad0fe7734 40 }
Mischa 0:337ad0fe7734 41
Mischa 0:337ad0fe7734 42 void DMAFuncGen::Setup(void) {
Mischa 0:337ad0fe7734 43 // Prepare the GPDMA system.
Mischa 0:337ad0fe7734 44 lli.srcAddr( (uint32_t) buffer );
Mischa 0:337ad0fe7734 45 lli.dstAddr( (uint32_t) &LPC_DAC->DACR );
Mischa 0:337ad0fe7734 46 lli.nextLLI( (uint32_t) &lli);
Mischa 0:337ad0fe7734 47 lli.control( dma.CxControl_TransferSize(buffer_size)
Mischa 0:337ad0fe7734 48 | dma.CxControl_SBSize((uint32_t)MODDMA::_1)
Mischa 0:337ad0fe7734 49 | dma.CxControl_DBSize((uint32_t)MODDMA::_1)
Mischa 0:337ad0fe7734 50 | dma.CxControl_SWidth((uint32_t)MODDMA::word)
Mischa 0:337ad0fe7734 51 | dma.CxControl_DWidth((uint32_t)MODDMA::word)
Mischa 0:337ad0fe7734 52 | dma.CxControl_SI()
Mischa 0:337ad0fe7734 53 | dma.CxControl_I() );
Mischa 0:337ad0fe7734 54
Mischa 0:337ad0fe7734 55 conf.srcMemAddr ( (uint32_t) buffer )
Mischa 0:337ad0fe7734 56 ->dstMemAddr ( MODDMA::DAC ) // unnecessary?
Mischa 0:337ad0fe7734 57 ->transferSize ( buffer_size )
Mischa 0:337ad0fe7734 58 ->transferType ( MODDMA::m2p )
Mischa 0:337ad0fe7734 59 ->dstConn ( MODDMA::DAC )
Mischa 0:337ad0fe7734 60 ->dmaLLI ( (uint32_t) &lli )
Mischa 0:337ad0fe7734 61 ->attach_tc ( this, &DMAFuncGen::TC_callback )
Mischa 0:337ad0fe7734 62 ->attach_err ( this, &DMAFuncGen::ERR_callback );
Mischa 0:337ad0fe7734 63
Mischa 0:337ad0fe7734 64 // Setup dma.
Mischa 0:337ad0fe7734 65 if (!dma.Setup( &conf )) {
Mischa 0:337ad0fe7734 66 error("Unexpected error during DMA.Setup(conf)");
Mischa 0:337ad0fe7734 67 }
Mischa 0:337ad0fe7734 68 }
Mischa 0:337ad0fe7734 69
Mischa 0:337ad0fe7734 70 float DMAFuncGen::Frequency() {
Mischa 0:337ad0fe7734 71 float f;
Mischa 0:337ad0fe7734 72 f=SystemCoreClock;
Mischa 0:337ad0fe7734 73 const int divisors[4] = {4,1,2,8};
Mischa 0:337ad0fe7734 74 f/=divisors[((LPC_SC->PCLKSEL0) >> 22) & 0x03];
Mischa 0:337ad0fe7734 75 f/=buffer_size;
Mischa 0:337ad0fe7734 76 f/=LPC_DAC->DACCNTVAL;
Mischa 0:337ad0fe7734 77 return f;
Mischa 0:337ad0fe7734 78 }
Mischa 0:337ad0fe7734 79
Mischa 0:337ad0fe7734 80 void DMAFuncGen::SetFrequency(float f) {
Mischa 0:337ad0fe7734 81 // Set the transfer frequency.
Mischa 0:337ad0fe7734 82 float cntval;
Mischa 0:337ad0fe7734 83 cntval = SystemCoreClock/(f*buffer_size);
Mischa 0:337ad0fe7734 84 const int PCLK_DAC[4] = {1,2,0,3};
Mischa 0:337ad0fe7734 85 int i=0;
Mischa 0:337ad0fe7734 86 int divisor=1;
Mischa 0:337ad0fe7734 87 while (((cntval/divisor)>65535) && (i<4)) {divisor*=2; i++; }
Mischa 0:337ad0fe7734 88 if (i==4) { divisor=8; i=3; }
Mischa 0:337ad0fe7734 89 LPC_SC->PCLKSEL0 &= ~(3UL<<22);
Mischa 0:337ad0fe7734 90 LPC_SC->PCLKSEL0 |= ((uint32_t) PCLK_DAC[i])<<22;
Mischa 0:337ad0fe7734 91 LPC_DAC->DACCNTVAL = cntval/divisor;
Mischa 0:337ad0fe7734 92 }
Mischa 0:337ad0fe7734 93
Mischa 0:337ad0fe7734 94 void DMAFuncGen::Start() {
Mischa 0:337ad0fe7734 95 dma.Enable( &conf );
Mischa 0:337ad0fe7734 96
Mischa 0:337ad0fe7734 97 // Enable DMA, and TC interrupt
Mischa 0:337ad0fe7734 98 LPC_DAC->DACCTRL = 3UL<<2; // DMA_ENA set, DMA_CNT set
Mischa 0:337ad0fe7734 99 }
Mischa 0:337ad0fe7734 100
Mischa 0:337ad0fe7734 101 void DMAFuncGen::Stop() {
Mischa 0:337ad0fe7734 102 dma.haltAndWaitChannelComplete( (MODDMA::CHANNELS) conf.channelNum() );
Mischa 0:337ad0fe7734 103 LPC_DAC->DACCTRL = 0UL<<2;
Mischa 0:337ad0fe7734 104 }
Mischa 0:337ad0fe7734 105
Mischa 0:337ad0fe7734 106 // Configuration callback on TC
Mischa 0:337ad0fe7734 107 void DMAFuncGen::TC_callback(void) {
Mischa 0:337ad0fe7734 108
Mischa 0:337ad0fe7734 109 // Just show sending buffer complete.
Mischa 0:337ad0fe7734 110 // led1 = !led1;
Mischa 0:337ad0fe7734 111
Mischa 0:337ad0fe7734 112 // Clear DMA IRQ flags.
Mischa 0:337ad0fe7734 113 if (dma.irqType() == MODDMA::TcIrq) dma.clearTcIrq();
Mischa 0:337ad0fe7734 114 }
Mischa 0:337ad0fe7734 115
Mischa 0:337ad0fe7734 116 // Configuration callback on Error
Mischa 0:337ad0fe7734 117 void DMAFuncGen::ERR_callback(void) {
Mischa 0:337ad0fe7734 118 error("Unexpected error - DMA error callback.");
Mischa 0:337ad0fe7734 119 }
Mischa 0:337ad0fe7734 120