Patrick Bader / SimpleDMA

A simple library to access the DMA functionality.

Fork of SimpleDMA by Erik -

SimpleDMA.h@0:d77ea45fa625, 2013-10-18 (annotated)

Committer:
Sissors
Date:
Fri Oct 18 07:44:42 2013 +0000
Revision:
0:d77ea45fa625
Child:
1:0b73b00bcee8
v0.1, KL25, no interrupt

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Sissors 0:d77ea45fa625 1 #ifndef SIMPLEDMA_H
Sissors 0:d77ea45fa625 2 #define SIMPLEDMA_H
Sissors 0:d77ea45fa625 3
Sissors 0:d77ea45fa625 4 #include "mbed.h"
Sissors 0:d77ea45fa625 5 #include "SimpleDMA_KL25.h"
Sissors 0:d77ea45fa625 6
Sissors 0:d77ea45fa625 7
Sissors 0:d77ea45fa625 8 /**
Sissors 0:d77ea45fa625 9 * SimpleDMA, DMA made simple! (Okay that was bad)
Sissors 0:d77ea45fa625 10 *
Sissors 0:d77ea45fa625 11 * A class to easily make basic DMA operations happen. Not all features
Sissors 0:d77ea45fa625 12 * of the DMA peripherals are used, but the main ones are: From and to memory
Sissors 0:d77ea45fa625 13 * and peripherals, either continiously or triggered
Sissors 0:d77ea45fa625 14 */
Sissors 0:d77ea45fa625 15 class SimpleDMA {
Sissors 0:d77ea45fa625 16 public:
Sissors 0:d77ea45fa625 17 SimpleDMA(int channel = 0);
Sissors 0:d77ea45fa625 18
Sissors 0:d77ea45fa625 19 /**
Sissors 0:d77ea45fa625 20 * Set the source of the DMA transfer
Sissors 0:d77ea45fa625 21 *
Sissors 0:d77ea45fa625 22 * Autoincrement increments the pointer after each transfer. If the source
Sissors 0:d77ea45fa625 23 * is an array this should be true, if it is a peripheral or a single memory
Sissors 0:d77ea45fa625 24 * location it should be false.
Sissors 0:d77ea45fa625 25 *
Sissors 0:d77ea45fa625 26 * The source can be any pointer to any memory location. Automatically
Sissors 0:d77ea45fa625 27 * the wordsize is calculated depending on the type, if required you can
Sissors 0:d77ea45fa625 28 * also override this.
Sissors 0:d77ea45fa625 29 *
Sissors 0:d77ea45fa625 30 * @param pointer - pointer to the memory location
Sissors 0:d77ea45fa625 31 * @param autoinc - should the pointer be incremented by the DMA module
Sissors 0:d77ea45fa625 32 * @param size - size of the transfer (optional, generally can be omitted)
Sissors 0:d77ea45fa625 33 * @return - 0 on success
Sissors 0:d77ea45fa625 34 */
Sissors 0:d77ea45fa625 35 template<typename Type>
Sissors 0:d77ea45fa625 36 int source(Type* pointer, bool autoinc, int size = sizeof(Type*)) {
Sissors 0:d77ea45fa625 37 return setMemory((uint32_t)pointer, size, true, autoinc);
Sissors 0:d77ea45fa625 38 }
Sissors 0:d77ea45fa625 39
Sissors 0:d77ea45fa625 40 /**
Sissors 0:d77ea45fa625 41 * Set the destination of the DMA transfer
Sissors 0:d77ea45fa625 42 *
Sissors 0:d77ea45fa625 43 * Autoincrement increments the pointer after each transfer. If the source
Sissors 0:d77ea45fa625 44 * is an array this should be true, if it is a peripheral or a single memory
Sissors 0:d77ea45fa625 45 * location it should be false.
Sissors 0:d77ea45fa625 46 *
Sissors 0:d77ea45fa625 47 * The destination can be any pointer to any memory location. Automatically
Sissors 0:d77ea45fa625 48 * the wordsize is calculated depending on the type, if required you can
Sissors 0:d77ea45fa625 49 * also override this.
Sissors 0:d77ea45fa625 50 *
Sissors 0:d77ea45fa625 51 * @param pointer - pointer to the memory location
Sissors 0:d77ea45fa625 52 * @param autoinc - should the pointer be incremented by the DMA module
Sissors 0:d77ea45fa625 53 * @param size - size of the transfer (optional, generally can be omitted)
Sissors 0:d77ea45fa625 54 * @return - 0 on success
Sissors 0:d77ea45fa625 55 */
Sissors 0:d77ea45fa625 56 template<typename Type>
Sissors 0:d77ea45fa625 57 int destination(Type* pointer, bool autoinc, int size = sizeof(Type*)) {
Sissors 0:d77ea45fa625 58 return setMemory((uint32_t)pointer, size, false, autoinc);
Sissors 0:d77ea45fa625 59 }
Sissors 0:d77ea45fa625 60
Sissors 0:d77ea45fa625 61 /**
Sissors 0:d77ea45fa625 62 * Set the trigger for the DMA operation
Sissors 0:d77ea45fa625 63 *
Sissors 0:d77ea45fa625 64 * In SimpleDMA_[yourdevice].h you can find the names of the different triggers.
Sissors 0:d77ea45fa625 65 * Trigger_ALWAYS is defined for all devices, it will simply move the data
Sissors 0:d77ea45fa625 66 * as fast as possible. Used for memory-memory transfers. If nothing else is set
Sissors 0:d77ea45fa625 67 * that will be used by default.
Sissors 0:d77ea45fa625 68 *
Sissors 0:d77ea45fa625 69 * @param trig - trigger to use
Sissors 0:d77ea45fa625 70 * @param return - 0 on success
Sissors 0:d77ea45fa625 71 */
Sissors 0:d77ea45fa625 72 int trigger(SimpleDMA_Trigger trig);
Sissors 0:d77ea45fa625 73
Sissors 0:d77ea45fa625 74 /**
Sissors 0:d77ea45fa625 75 * Start the transfer
Sissors 0:d77ea45fa625 76 *
Sissors 0:d77ea45fa625 77 * @param length - number of BYTES to be moved by the DMA
Sissors 0:d77ea45fa625 78 */
Sissors 0:d77ea45fa625 79 int start(int length);
Sissors 0:d77ea45fa625 80
Sissors 0:d77ea45fa625 81 /**
Sissors 0:d77ea45fa625 82 * Set the DMA channel
Sissors 0:d77ea45fa625 83 *
Sissors 0:d77ea45fa625 84 * @param chan - DMA channel to use
Sissors 0:d77ea45fa625 85 */
Sissors 0:d77ea45fa625 86 void channel(int chan);
Sissors 0:d77ea45fa625 87
Sissors 0:d77ea45fa625 88 /**
Sissors 0:d77ea45fa625 89 * Is the DMA channel busy
Sissors 0:d77ea45fa625 90 *
Sissors 0:d77ea45fa625 91 * @return - true if it is busy
Sissors 0:d77ea45fa625 92 */
Sissors 0:d77ea45fa625 93 bool isBusy( void );
Sissors 0:d77ea45fa625 94
Sissors 0:d77ea45fa625 95
Sissors 0:d77ea45fa625 96
Sissors 0:d77ea45fa625 97
Sissors 0:d77ea45fa625 98
Sissors 0:d77ea45fa625 99 protected:
Sissors 0:d77ea45fa625 100 int setMemory(uint32_t address, int wordsize, bool source, bool autoinc);
Sissors 0:d77ea45fa625 101 int _channel;
Sissors 0:d77ea45fa625 102
Sissors 0:d77ea45fa625 103
Sissors 0:d77ea45fa625 104
Sissors 0:d77ea45fa625 105 };
Sissors 0:d77ea45fa625 106 #endif