Mischa Megens / DMAFuncGen

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Dependents:   DACDMAfuncgenlib

DMAFuncGen.h@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 #ifndef MBED_DMAFUNCGEN_H
Mischa 0:337ad0fe7734 2 #define MBED_DMAFUNCGEN_H
Mischa 0:337ad0fe7734 3
Mischa 0:337ad0fe7734 4 #include "mbed.h"
Mischa 0:337ad0fe7734 5 #include "MODDMA.h"
Mischa 0:337ad0fe7734 6
Mischa 0:337ad0fe7734 7 //! DMAFuncGen class generates a waveform on Analog output using Direct Memory Access alone.
Mischa 0:337ad0fe7734 8 class DMAFuncGen {
Mischa 0:337ad0fe7734 9 public:
Mischa 0:337ad0fe7734 10 /// Create DMAFucGen instance
Mischa 0:337ad0fe7734 11 /// @param dma The dma to use.
Mischa 0:337ad0fe7734 12 /// @param channel The dma channel to use for transferring data to the D/A converter.
Mischa 0:337ad0fe7734 13 DMAFuncGen(MODDMA& dma, MODDMA::CHANNELS channel);
Mischa 0:337ad0fe7734 14
Mischa 0:337ad0fe7734 15 /// Number of data points in the waveform. Must be set by client.
Mischa 0:337ad0fe7734 16 int buffer_size;
Mischa 0:337ad0fe7734 17 /// Buffer for the binary data that will be transferred by DMA. Must be allocated by client.
Mischa 0:337ad0fe7734 18 uint32_t* buffer;
Mischa 0:337ad0fe7734 19
Mischa 0:337ad0fe7734 20 /// Set waveform value for a specified data point.
Mischa 0:337ad0fe7734 21 /// @param idx The index of the data point in #buffer, must be in range 0..#buffer_size-1.
Mischa 0:337ad0fe7734 22 /// @param x The value for the D/A, in the range 0..65535.
Mischa 0:337ad0fe7734 23 void set(int idx, uint16_t x);
Mischa 0:337ad0fe7734 24 /// Get waveform value for a specified data point
Mischa 0:337ad0fe7734 25 /// @param idx The index of the data point in the #buffer, in the range 0..#buffer_size-1.
Mischa 0:337ad0fe7734 26 /// @returns The value for the data point, in the range 0..65535.
Mischa 0:337ad0fe7734 27 uint16_t operator[](const uint16_t idx);
Mischa 0:337ad0fe7734 28
Mischa 0:337ad0fe7734 29 /// Connect the D/A converter pin (enable output)
Mischa 0:337ad0fe7734 30 void Connect();
Mischa 0:337ad0fe7734 31 /// Disconnect the D/A converter pin (pin becomes tri-state)
Mischa 0:337ad0fe7734 32 void Disconnect();
Mischa 0:337ad0fe7734 33
Mischa 0:337ad0fe7734 34 /// Reference to the DMA instance
Mischa 0:337ad0fe7734 35 MODDMA& dma;
Mischa 0:337ad0fe7734 36
Mischa 0:337ad0fe7734 37 /// Set up the dma.
Mischa 0:337ad0fe7734 38 /// Must set #buffer and #buffer_size first.
Mischa 0:337ad0fe7734 39 void Setup(void);
Mischa 0:337ad0fe7734 40
Mischa 0:337ad0fe7734 41 /// Set waveform frequency
Mischa 0:337ad0fe7734 42 /// @note Must set #buffer_size first.
Mischa 0:337ad0fe7734 43 /// @param f Frequency of a complete cycle of the waveform (in Hz).
Mischa 0:337ad0fe7734 44 void SetFrequency(float f);
Mischa 0:337ad0fe7734 45 /// Read the actual waveform frequency that will be generated.
Mischa 0:337ad0fe7734 46 float Frequency();
Mischa 0:337ad0fe7734 47
Mischa 0:337ad0fe7734 48 /// Start generating the waveform (start dma)
Mischa 0:337ad0fe7734 49 void Start();
Mischa 0:337ad0fe7734 50 /// Stop generating the waveform (but waits for the current cycle to complete)
Mischa 0:337ad0fe7734 51 void Stop();
Mischa 0:337ad0fe7734 52
Mischa 0:337ad0fe7734 53 private:
Mischa 0:337ad0fe7734 54 MODDMA_Config conf;
Mischa 0:337ad0fe7734 55 MODDMA_LLI lli;
Mischa 0:337ad0fe7734 56
Mischa 0:337ad0fe7734 57 /// ISR routine, called on Terminal Count
Mischa 0:337ad0fe7734 58 void TC_callback(void);
Mischa 0:337ad0fe7734 59 /// ISR routine, called on dma ERRor
Mischa 0:337ad0fe7734 60 void ERR_callback(void);
Mischa 0:337ad0fe7734 61 };
Mischa 0:337ad0fe7734 62
Mischa 0:337ad0fe7734 63 #endif