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Signal Generator
Dependencies: IniManager RA8875 Watchdog mbed-rtos mbed
Fork of speaker_demo_Analog by
SignalGenDAC.h
- Committer:
- WiredHome
- Date:
- 2017-05-20
- Revision:
- 6:1f48212fbaf9
- Parent:
- 5:49dd0c647a40
File content as of revision 6:1f48212fbaf9:
// // Signal Generator DAC Driver // // Derived from AN10917: Memory to DAC data transfers using the LPC1700's DMA // // #ifndef SIGNALGENDAC_H #define SIGNALGENDAC_H #include "mbed.h" #include "SignalGenDefs.h" // access the waveform mode data type #define SIGNAL_MEM_ENTRIES 2048 // size of the DAC buffer /// The Signal Generator DAC Driver /// /// This class provides the interface to first configure the DAC hardware characteristics, /// and then to define and control the DAC output. /// /// A choice of waveforms is available (Sine, Square, Triangle, Sawtooth, and User Defined. /// /// @todo add support for User Defined waveform. /// /// @code /// SignalGenDAC g_signal; // defaults to LPC1768 mbed module (p18 and 3.3v) /// /// g_signal.PrepareWaveform(SG_SINE, 1000, 50, 2.2, 1.5); /// g_signal.Start(); /// wait_ms(1000); /// g_signal.Stop(); /// @endcode /// class SignalGenDAC { public: /// Constructor, which is used to define the hardware /// /// The default parameters are based on the mbed LPC1768 micro, which has /// AnalogOut on p18 and uses a 3.3v supply for the A/D reference. /// /// @param[in] aout is the analog output pin /// @param[in] minV is based on the A/D low reference voltage (default 0.0) /// @param[in] maxV is based on the A/D high reference voltage (default 3.3) /// SignalGenDAC(PinName aout = p18, float minV = 0.0, float maxV = 3.3); /// Destructor /// ~SignalGenDAC(); /// Create the waveform in the private memory buffer that is used to DMA to the DAC /// /// @param[in] mode defines the waveform: Sine, Square, Triangle, Sawtooth, User /// @param[in] frequency defines the desired frequency /// @param[in] dutycycle defined the duty cycle of the waveform to be created. The value /// is range limited to 5 to 95 (representing 5 to 95 %). /// @param[in] voltage is the peak-to-peak voltage, and it range limited to 0 to 3.0. /// @param[in] offset is the offset voltage, and is range limited to 0 to 3.0. /// void PrepareWaveform(SG_Waveform mode, float frequency, float dutycycle, float voltage, float offset); /// Start the signal, in either a oneshot, or continuous mode. /// /// @param[in] oneShot defaults false, which causes continuous mode. /// When set true, one cycle is produced. /// void Start(bool oneShot = false); /// Stop the signal, if it is running. /// void Stop(void); /// Determine if the signal is running. /// /// @returns true if the signal is running. /// bool isRunning(void) { return isOn; } private: bool isOn; // tracks whether the signal is on or off AnalogOut * aout; float frequency; // signal parameters float dutycycle; float voltage; float offset; float minV; // Based on the A/D hardware float maxV; // Based on the A/D hardware /// range limit a value. float rangelimit(float value, float min, float max); int numSamples; // private container for number of samples }; #endif // SIGNALGENDAC_H