File content as of revision 59:1cfd9d9fb99d:

/**
 *  Setup triggering for DMA2 and PortC
 */
#include "dma.h"

#define TOTAL_SAMPLES 256
int len = TOTAL_SAMPLES;
uint16_t sample_array0[TOTAL_SAMPLES];
uint16_t sample_array1[TOTAL_SAMPLES];

uint16_t static_input_array0[TOTAL_SAMPLES];
uint16_t static_input_array1[TOTAL_SAMPLES];

uint16_t static_output_array0[TOTAL_SAMPLES];
uint16_t output_array0[TOTAL_SAMPLES];

uint16_t sampling_status;
uint16_t sampling_status_done = 1;

void dma_init()
{
    // Enable clock for DMAMUX and DMA - all the peripherals need clocks to function
    SIM_SCGC6 |= SIM_SCGC6_DMAMUX_MASK;
    SIM_SCGC7 |= SIM_SCGC7_DMA_MASK;  


    // Enable DMA channels and select MUX to the correct source (see page 95 of user manual
    DMAMUX_CHCFG0 = 0;
    DMAMUX_CHCFG1 = 0;
  
    
    // Enable request signal for channel 0, 1
    DMA_ERQ = 0;
    DMA_ERQ = DMA_ERQ_ERQ0_MASK | DMA_ERQ_ERQ1_MASK;
    
    // select round-robin arbitration priority
    DMA_CR |= DMA_CR_ERCA_MASK;
    
    // Disable minor loop
    DMA_CR &= ~DMA_CR_EMLM_MASK;

// DMA setup for ADC sampling    
    // Set memory address for source and destination for DMA0 and DMA1
    DMA_TCD0_SADDR = (uint32_t) &ADC0_RA;
    DMA_TCD0_DADDR = (uint32_t) sample_array0;
    DMA_TCD1_SADDR = (uint32_t) &ADC1_RA;
    DMA_TCD1_DADDR = (uint32_t) sample_array1;
    
    // Set an offset for source and destination address
    DMA_TCD0_SOFF = 0x00; // Source address offset of 0 bytes per transaction
    DMA_TCD0_DOFF = 0x02; // Destination address offset of 2 bytes per transaction
    DMA_TCD1_SOFF = 0x00; // Source address offset of 0 bytes per transaction
    DMA_TCD1_DOFF = 0x02; // Destination address offset of 2 bytes per transaction
        
    // Set source and destination data transfer size
    DMA_TCD0_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
    DMA_TCD1_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
        
    // Number of bytes to be transfered in each service request of the channel
    DMA_TCD0_NBYTES_MLNO = 0x02;
    DMA_TCD1_NBYTES_MLNO = 0x02;
        
    // Major iteration count
    DMA_TCD0_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
    DMA_TCD0_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
    DMA_TCD1_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
    DMA_TCD1_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
    
    // Adjustment value used to restore the source and destiny address to the initial value
    // After reading 'len' number of times, the DMA goes back to the beginning by subtracting len*2 from the address (going back to the original address)
    
    DMA_TCD0_SLAST = 0;      // Source address adjustment
    DMA_TCD0_DLASTSGA = -len*2;  // Destination address adjustment
    DMA_TCD1_SLAST = 0;      // Source address adjustment
    DMA_TCD1_DLASTSGA = -len*2;  // Destination address adjustment
//    DMA_TCD2_SLAST = 0;      // Source address adjustment
//    DMA_TCD2_DLASTSGA = -len*2;  // Destination address adjustment

    DMAMUX_CHCFG0 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_SOURCE(40); // ADC0
    DMAMUX_CHCFG1 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_SOURCE(41); // ADC1
    /* Source number    Source module
           40                ADC0
           41                ADC1
    */

   
    // Setup control and status register
    DMA_TCD0_CSR = 0;
    DMA_TCD1_CSR = 0;

//
// Now set up DAC DMA outputs from the output array
//
    DMA_ERQ |= DMA_ERQ_ERQ2_MASK;    
    //DMA_TCD1_CSR |= DMA_CSR_MAJORLINKCH(2) | DMA_CSR_MAJORELINK_MASK;    
    
    // Set memory address for source and destination for DMA0 and DMA1
    DMA_TCD2_SADDR = (uint32_t) output_array0;
    DMA_TCD2_DADDR = (uint32_t) &DAC0_DAT0L;
    
    // Set an offset for source and destination address
    DMA_TCD2_SOFF = 0x02; // Source address offset of 1 per transaction
    DMA_TCD2_DOFF = 0x00; // Destination address offset of 0 bytes per transaction
        
    // Set source and destination data transfer size
    DMA_TCD2_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
        
    // Number of bytes to be transfered in each service request of the channel
    DMA_TCD2_NBYTES_MLNO = 0x02;
        
    // Major iteration count
    DMA_TCD2_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
    DMA_TCD2_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
    
    // Adjustment value used to restore the source and destiny address to the initial value
    // After reading 'len' number of times, the DMA goes back to the beginning by subtracting len*2 from the address (going back to the original address)
    
    DMA_TCD2_SLAST = -len*2;      // Source address adjustment
    DMA_TCD2_DLASTSGA = 0;  // Destination address adjustment

    DMAMUX_CHCFG2 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_SOURCE(48); // PDB source

    DMA_TCD2_CSR = 0;
//
// Now set up static dataset linking once the ADC samples are recorded
//
    // DMA Channels 4 and 5 now will be enabled
    DMA_ERQ |= DMA_ERQ_ERQ4_MASK | DMA_ERQ_ERQ5_MASK;
    DMA_TCD2_CSR |= DMA_CSR_MAJORLINKCH(4) | DMA_CSR_MAJORELINK_MASK;

    // Set memory address for source and destination for DMA4 and DMA5
    DMA_TCD4_SADDR = (uint32_t) sample_array0;
    DMA_TCD4_DADDR = (uint32_t) static_input_array0;
    DMA_TCD5_SADDR = (uint32_t) sample_array1;
    DMA_TCD5_DADDR = (uint32_t) static_input_array1;
    
    // Set an offset for source and destination address
    DMA_TCD4_SOFF = 0x02; // Source address offset of 2 bits per transaction
    DMA_TCD4_DOFF = 0x02; // Destination address offset of 1 bit per transaction
    DMA_TCD5_SOFF = 0x02; // Source address offset of 2 bits per transaction
    DMA_TCD5_DOFF = 0x02; // Destination address offset of 1 bit per transaction
        
    // Set source and destination data transfer size
    DMA_TCD4_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
    DMA_TCD5_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
        
    // Number of bytes to be transfered in each service request of the channel
    //DMA_TCD4_NBYTES_MLNO = 0x02 * TOTAL_SAMPLES;
    //DMA_TCD5_NBYTES_MLNO = 0x02 * TOTAL_SAMPLES;
    DMA_TCD4_NBYTES_MLNO = 0x02 * len; 
    DMA_TCD5_NBYTES_MLNO = 0x02 * len; 
        
    // Current major iteration count
    DMA_TCD4_CITER_ELINKNO = 0x01;
    DMA_TCD4_BITER_ELINKNO = 0x01;
    DMA_TCD5_CITER_ELINKNO = 0x01;
    DMA_TCD5_BITER_ELINKNO = 0x01;
    
    // Adjustment value used to restore the source and destiny address to the initial value
    // After reading 'len' number of times, the DMA goes back to the beginning by subtracting len*2 from the address (going back to the original address)
    
    DMA_TCD4_SLAST = -len*2;      // Source address adjustment
    DMA_TCD4_DLASTSGA = -len*2;  // Destination address adjustment
    DMA_TCD5_SLAST = -len*2;      // Source address adjustment
    DMA_TCD5_DLASTSGA = -len*2;  // Destination address adjustment

    DMA_TCD4_CSR = 0;
    DMA_TCD4_CSR |= DMA_CSR_MAJORLINKCH(5) | DMA_CSR_MAJORELINK_MASK;
    DMA_TCD5_CSR = 0;

//
// Now set up linking from static DAC to memory for output through DMA
//
    // DMA Channel 6 will be enabled

    DMA_ERQ |= DMA_ERQ_ERQ6_MASK;
    DMA_TCD5_CSR |= DMA_CSR_MAJORLINKCH(6) | DMA_CSR_MAJORELINK_MASK;

    // Set memory address for source and destination for DMA6
    DMA_TCD6_SADDR = (uint32_t) static_output_array0;
    DMA_TCD6_DADDR = (uint32_t) output_array0;
    
    // Set an offset for source and destination address
    DMA_TCD6_SOFF = 0x02; // Source address offset of 2 bits per transaction
    DMA_TCD6_DOFF = 0x02; // Destination address offset of 1 bit per transaction
        
    // Set source and destination data transfer size
    DMA_TCD6_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
    DMA_TCD6_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
        
    // Number of bytes to be transfered in each service request of the channel
    DMA_TCD6_NBYTES_MLNO = 0x02 * len; 
        
    // Current major iteration count
    DMA_TCD6_CITER_ELINKNO = 0x01;
    DMA_TCD6_BITER_ELINKNO = 0x01;
    
    // Adjustment value used to restore the source and destiny address to the initial value
    // After reading 'len' number of times, the DMA goes back to the beginning by subtracting len*2 from the address (going back to the original address)
    
    DMA_TCD6_SLAST = -len*2;      // Source address adjustment
    DMA_TCD6_DLASTSGA = -len*2;  // Destination address adjustment

    DMA_TCD6_CSR = 0;
    
//
// Provide status
//    

    // DMA Channel 8
    DMA_ERQ |= DMA_ERQ_ERQ8_MASK;
    DMA_TCD6_CSR |= DMA_CSR_MAJORLINKCH(8) | DMA_CSR_MAJORELINK_MASK;
    
    // Set memory address for source and destiantion for DMA 8
    DMA_TCD8_SADDR = (uint32_t) &sampling_status_done;
    DMA_TCD8_DADDR = (uint32_t) &sampling_status;
    
    // Set an offset for source and destination address
    DMA_TCD8_SOFF = 0x00; // Source address offset of 2 bits per transaction
    DMA_TCD8_DOFF = 0x00; // Destination address offset of 1 bit per transaction
        
    // Set source and destination data transfer size
    DMA_TCD8_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
    DMA_TCD8_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
        
    // Number of bytes to be transfered in each service request of the channel
    DMA_TCD8_NBYTES_MLNO = 0x02; 
        
    // Current major iteration count
    DMA_TCD8_CITER_ELINKNO = 0x01;
    DMA_TCD8_BITER_ELINKNO = 0x01;
    
    // Adjustment value used to restore the source and destiny address to the initial value
    // After reading 'len' number of times, the DMA goes back to the beginning by subtracting len*2 from the address (going back to the original address)
    
    DMA_TCD8_SLAST = 0;      // Source address adjustment
    DMA_TCD8_DLASTSGA = 0;  // Destination address adjustment

    DMA_TCD8_CSR = 0;
    
}

void dma_reset() {
    // Set memory address for destinations back to the beginning
    dma_init();
}




/*pc.printf("DMA_CR: %08x\r\n", DMA_CR);
    pc.printf("DMA_ES: %08x\r\n", DMA_ES);
    pc.printf("DMA_ERQ: %08x\r\n", DMA_ERQ);
    pc.printf("DMA_EEI: %08x\r\n", DMA_EEI);
    pc.printf("DMA_CEEI: %02x\r\n", DMA_CEEI);
    pc.printf("DMA_SEEI: %02x\r\n", DMA_SEEI);
    pc.printf("DMA_CERQ: %02x\r\n", DMA_CERQ);
    pc.printf("DMA_SERQ: %02x\r\n", DMA_SERQ);
    pc.printf("DMA_CDNE: %02x\r\n", DMA_CDNE);
    pc.printf("DMA_SSRT: %02x\r\n", DMA_SSRT);
    pc.printf("DMA_CERR: %02x\r\n", DMA_CERR);
    pc.printf("DMA_CINT: %02x\r\n", DMA_CINT);
    pc.printf("DMA_INT: %08x\r\n", DMA_INT);
    pc.printf("DMA_ERR: %08x\r\n", DMA_ERR);
    pc.printf("DMA_HRS: %08x\r\n", DMA_HRS);*/