Jared Baxter / Mbed 2 deprecated Impedance_Fast_Circuitry_print_V_I

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Dependencies:   mbed-dsp mbed

Fork of Impedance_Fast_Circuitry by Jared Baxter

dma.cpp@46:a015ebf4663b, 2015-01-31 (annotated)

Committer:
timmey9
Date:
Sat Jan 31 08:13:33 2015 +0000
Revision:
46:a015ebf4663b
Parent:
45:d591d138cdeb
Child:
48:29f14bc30ba6
DMA is reading from FTM2_CNT.  Still need to get PDB triggering the DMAs.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
timmey9 45:d591d138cdeb 1 /**
timmey9 45:d591d138cdeb 2 * Setup triggering for DMA2 and PortC
timmey9 34:44cc9b76a507 3 */
timmey9 34:44cc9b76a507 4 #include "dma.h"
timmey9 34:44cc9b76a507 5
timmey9 45:d591d138cdeb 6 #define TOTAL_SAMPLES 10
timmey9 45:d591d138cdeb 7 int len = TOTAL_SAMPLES;
timmey9 45:d591d138cdeb 8 uint16_t sample_array0[TOTAL_SAMPLES];
timmey9 45:d591d138cdeb 9 uint16_t sample_array1[TOTAL_SAMPLES];
timmey9 45:d591d138cdeb 10 uint16_t angle_array[TOTAL_SAMPLES];
timmey9 46:a015ebf4663b 11 //DigitalIn AMT20_A(PTB18); // FTM2_QD_PHA, apparently the k64f has a quadrature decoder. look into this (page 264)
timmey9 46:a015ebf4663b 12 //DigitalIn AMT20_B(PTB10); // FTM2_QD_PHB
timmey9 45:d591d138cdeb 13
timmey9 45:d591d138cdeb 14 void dma_init()
timmey9 34:44cc9b76a507 15 {
timmey9 34:44cc9b76a507 16 // Enable clock for DMAMUX and DMA
timmey9 34:44cc9b76a507 17 SIM_SCGC6 |= SIM_SCGC6_DMAMUX_MASK;
timmey9 45:d591d138cdeb 18 SIM_SCGC7 |= SIM_SCGC7_DMA_MASK;
timmey9 46:a015ebf4663b 19 SIM_SCGC6 |= SIM_SCGC6_FTM2_MASK; // make sure clock is enabled for FTM2
timmey9 34:44cc9b76a507 20
timmey9 45:d591d138cdeb 21 // Enable DMA channels and select MUX to the correct source (see page 95 of user manual
timmey9 45:d591d138cdeb 22 DMAMUX_CHCFG0 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_SOURCE(40); // ADC0
timmey9 45:d591d138cdeb 23 DMAMUX_CHCFG1 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_SOURCE(41); // ADC1
timmey9 46:a015ebf4663b 24 DMAMUX_CHCFG2 |= DMAMUX_CHCFG_ENBL_MASK | DMAMUX_CHCFG_TRIG_MASK | DMAMUX_CHCFG_SOURCE(48);
timmey9 46:a015ebf4663b 25 /* Source number Source module Source description
timmey9 46:a015ebf4663b 26 30 FTM2 Channel 0
timmey9 46:a015ebf4663b 27 31 FTM2 Channel 1
timmey9 46:a015ebf4663b 28 48 PDB -
timmey9 46:a015ebf4663b 29 */
timmey9 36:07d8a3143967 30
timmey9 36:07d8a3143967 31
timmey9 34:44cc9b76a507 32 // Enable request signal for channel 0
timmey9 36:07d8a3143967 33 DMA_ERQ = DMA_ERQ_ERQ0_MASK | DMA_ERQ_ERQ1_MASK | DMA_ERQ_ERQ2_MASK;
timmey9 45:d591d138cdeb 34
timmey9 45:d591d138cdeb 35 // select round-robin arbitration priority
timmey9 45:d591d138cdeb 36 DMA_CR |= DMA_CR_ERCA_MASK;
timmey9 45:d591d138cdeb 37
timmey9 36:07d8a3143967 38 // Set memory address for source and destination for DMA0, DMA1, and DMA2
timmey9 45:d591d138cdeb 39 DMA_TCD0_SADDR = (uint32_t) &ADC0_RA;
timmey9 45:d591d138cdeb 40 DMA_TCD0_DADDR = (uint32_t) sample_array0;
timmey9 45:d591d138cdeb 41 DMA_TCD1_SADDR = (uint32_t) &ADC1_RA;
timmey9 45:d591d138cdeb 42 DMA_TCD1_DADDR = (uint32_t) sample_array1;
timmey9 45:d591d138cdeb 43 DMA_TCD2_SADDR = (uint32_t) &FTM2_CNT;
timmey9 45:d591d138cdeb 44 DMA_TCD2_DADDR = (uint32_t) angle_array;
timmey9 36:07d8a3143967 45
timmey9 34:44cc9b76a507 46 // Set an offset for source and destination address
timmey9 34:44cc9b76a507 47 DMA_TCD0_SOFF = 0x00; // Source address offset of 2 bits per transaction
timmey9 34:44cc9b76a507 48 DMA_TCD0_DOFF = 0x02; // Destination address offset of 1 bit per transaction
timmey9 36:07d8a3143967 49 DMA_TCD1_SOFF = 0x00; // Source address offset of 2 bits per transaction
timmey9 36:07d8a3143967 50 DMA_TCD1_DOFF = 0x02; // Destination address offset of 1 bit per transaction
timmey9 36:07d8a3143967 51 DMA_TCD2_SOFF = 0x00; // Source address offset of 2 bits per transaction
timmey9 36:07d8a3143967 52 DMA_TCD2_DOFF = 0x02; // Destination address offset of 1 bit per transaction
timmey9 34:44cc9b76a507 53
timmey9 34:44cc9b76a507 54 // Set source and destination data transfer size
timmey9 34:44cc9b76a507 55 DMA_TCD0_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
timmey9 36:07d8a3143967 56 DMA_TCD1_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
timmey9 36:07d8a3143967 57 DMA_TCD2_ATTR = DMA_ATTR_SSIZE(1) | DMA_ATTR_DSIZE(1);
timmey9 34:44cc9b76a507 58
timmey9 34:44cc9b76a507 59 // Number of bytes to be transfered in each service request of the channel
timmey9 34:44cc9b76a507 60 DMA_TCD0_NBYTES_MLNO = 0x02;
timmey9 36:07d8a3143967 61 DMA_TCD1_NBYTES_MLNO = 0x02;
timmey9 36:07d8a3143967 62 DMA_TCD2_NBYTES_MLNO = 0x02;
timmey9 34:44cc9b76a507 63
timmey9 34:44cc9b76a507 64 // Current major iteration count (a single iteration of 5 bytes)
timmey9 45:d591d138cdeb 65 DMA_TCD0_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
timmey9 45:d591d138cdeb 66 DMA_TCD0_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
timmey9 45:d591d138cdeb 67 DMA_TCD1_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
timmey9 45:d591d138cdeb 68 DMA_TCD1_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
timmey9 45:d591d138cdeb 69 DMA_TCD2_CITER_ELINKNO = DMA_CITER_ELINKNO_CITER(len);
timmey9 45:d591d138cdeb 70 DMA_TCD2_BITER_ELINKNO = DMA_BITER_ELINKNO_BITER(len);
timmey9 34:44cc9b76a507 71
timmey9 34:44cc9b76a507 72 // Adjustment value used to restore the source and destiny address to the initial value
timmey9 45:d591d138cdeb 73 // 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)
timmey9 45:d591d138cdeb 74
timmey9 44:41c262caf898 75 DMA_TCD0_SLAST = 0; // Source address adjustment
timmey9 45:d591d138cdeb 76 DMA_TCD0_DLASTSGA = -len*2; // Destination address adjustment
timmey9 44:41c262caf898 77 DMA_TCD1_SLAST = 0; // Source address adjustment
timmey9 45:d591d138cdeb 78 DMA_TCD1_DLASTSGA = -len*2; // Destination address adjustment
timmey9 44:41c262caf898 79 DMA_TCD2_SLAST = 0; // Source address adjustment
timmey9 45:d591d138cdeb 80 DMA_TCD2_DLASTSGA = -len*2; // Destination address adjustment
timmey9 34:44cc9b76a507 81
timmey9 34:44cc9b76a507 82 // Setup control and status register
timmey9 34:44cc9b76a507 83 DMA_TCD0_CSR = 0;
timmey9 36:07d8a3143967 84 DMA_TCD1_CSR = 0;
timmey9 46:a015ebf4663b 85 DMA_TCD2_CSR = 0;
timmey9 39:82dc3daecf32 86
timmey9 45:d591d138cdeb 87
timmey9 40:bd6d8c35e822 88 /*pc.printf("DMA_CR: %08x\r\n", DMA_CR);
timmey9 39:82dc3daecf32 89 pc.printf("DMA_ES: %08x\r\n", DMA_ES);
timmey9 39:82dc3daecf32 90 pc.printf("DMA_ERQ: %08x\r\n", DMA_ERQ);
timmey9 39:82dc3daecf32 91 pc.printf("DMA_EEI: %08x\r\n", DMA_EEI);
timmey9 39:82dc3daecf32 92 pc.printf("DMA_CEEI: %02x\r\n", DMA_CEEI);
timmey9 39:82dc3daecf32 93 pc.printf("DMA_SEEI: %02x\r\n", DMA_SEEI);
timmey9 39:82dc3daecf32 94 pc.printf("DMA_CERQ: %02x\r\n", DMA_CERQ);
timmey9 39:82dc3daecf32 95 pc.printf("DMA_SERQ: %02x\r\n", DMA_SERQ);
timmey9 39:82dc3daecf32 96 pc.printf("DMA_CDNE: %02x\r\n", DMA_CDNE);
timmey9 39:82dc3daecf32 97 pc.printf("DMA_SSRT: %02x\r\n", DMA_SSRT);
timmey9 39:82dc3daecf32 98 pc.printf("DMA_CERR: %02x\r\n", DMA_CERR);
timmey9 39:82dc3daecf32 99 pc.printf("DMA_CINT: %02x\r\n", DMA_CINT);
timmey9 39:82dc3daecf32 100 pc.printf("DMA_INT: %08x\r\n", DMA_INT);
timmey9 39:82dc3daecf32 101 pc.printf("DMA_ERR: %08x\r\n", DMA_ERR);
timmey9 40:bd6d8c35e822 102 pc.printf("DMA_HRS: %08x\r\n", DMA_HRS);*/
timmey9 34:44cc9b76a507 103 }
timmey9 40:bd6d8c35e822 104
timmey9 45:d591d138cdeb 105 void dma_reset() {
timmey9 40:bd6d8c35e822 106 // Set memory address for destinations back to the beginning
timmey9 45:d591d138cdeb 107 dma_init();
timmey9 40:bd6d8c35e822 108 }