David Smart / Mbed 2 deprecated SignalGenerator

Signal Generator

Dependencies:   IniManager RA8875 Watchdog mbed-rtos mbed

Fork of speaker_demo_Analog by jim hamblen

SignalGenDAC.h@6:1f48212fbaf9, 2017-05-20 (annotated)

Committer:
WiredHome
Date:
Sat May 20 19:52:23 2017 +0000
Revision:
6:1f48212fbaf9
Parent:
5:49dd0c647a40 
Signal Generator - a work in process as the need arises.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
WiredHome 6:1f48212fbaf9 1 //
WiredHome 6:1f48212fbaf9 2 // Signal Generator DAC Driver
WiredHome 2:8f71b71fce1b 3 //
WiredHome 2:8f71b71fce1b 4 // Derived from AN10917: Memory to DAC data transfers using the LPC1700's DMA
WiredHome 2:8f71b71fce1b 5 //
WiredHome 6:1f48212fbaf9 6 //
WiredHome 2:8f71b71fce1b 7 #ifndef SIGNALGENDAC_H
WiredHome 2:8f71b71fce1b 8 #define SIGNALGENDAC_H
WiredHome 2:8f71b71fce1b 9
WiredHome 2:8f71b71fce1b 10 #include "mbed.h"
WiredHome 2:8f71b71fce1b 11
WiredHome 2:8f71b71fce1b 12 #include "SignalGenDefs.h" // access the waveform mode data type
WiredHome 2:8f71b71fce1b 13
WiredHome 2:8f71b71fce1b 14
WiredHome 2:8f71b71fce1b 15 #define SIGNAL_MEM_ENTRIES 2048 // size of the DAC buffer
WiredHome 2:8f71b71fce1b 16
WiredHome 6:1f48212fbaf9 17 /// The Signal Generator DAC Driver
WiredHome 6:1f48212fbaf9 18 ///
WiredHome 6:1f48212fbaf9 19 /// This class provides the interface to first configure the DAC hardware characteristics,
WiredHome 6:1f48212fbaf9 20 /// and then to define and control the DAC output.
WiredHome 6:1f48212fbaf9 21 ///
WiredHome 6:1f48212fbaf9 22 /// A choice of waveforms is available (Sine, Square, Triangle, Sawtooth, and User Defined.
WiredHome 6:1f48212fbaf9 23 ///
WiredHome 6:1f48212fbaf9 24 /// @todo add support for User Defined waveform.
WiredHome 6:1f48212fbaf9 25 ///
WiredHome 6:1f48212fbaf9 26 /// @code
WiredHome 6:1f48212fbaf9 27 /// SignalGenDAC g_signal; // defaults to LPC1768 mbed module (p18 and 3.3v)
WiredHome 6:1f48212fbaf9 28 ///
WiredHome 6:1f48212fbaf9 29 /// g_signal.PrepareWaveform(SG_SINE, 1000, 50, 2.2, 1.5);
WiredHome 6:1f48212fbaf9 30 /// g_signal.Start();
WiredHome 6:1f48212fbaf9 31 /// wait_ms(1000);
WiredHome 6:1f48212fbaf9 32 /// g_signal.Stop();
WiredHome 6:1f48212fbaf9 33 /// @endcode
WiredHome 6:1f48212fbaf9 34 ///
WiredHome 2:8f71b71fce1b 35 class SignalGenDAC {
WiredHome 2:8f71b71fce1b 36
WiredHome 2:8f71b71fce1b 37 public:
WiredHome 2:8f71b71fce1b 38
WiredHome 2:8f71b71fce1b 39 /// Constructor, which is used to define the hardware
WiredHome 5:49dd0c647a40 40 ///
WiredHome 5:49dd0c647a40 41 /// The default parameters are based on the mbed LPC1768 micro, which has
WiredHome 5:49dd0c647a40 42 /// AnalogOut on p18 and uses a 3.3v supply for the A/D reference.
WiredHome 2:8f71b71fce1b 43 ///
WiredHome 2:8f71b71fce1b 44 /// @param[in] aout is the analog output pin
WiredHome 2:8f71b71fce1b 45 /// @param[in] minV is based on the A/D low reference voltage (default 0.0)
WiredHome 5:49dd0c647a40 46 /// @param[in] maxV is based on the A/D high reference voltage (default 3.3)
WiredHome 2:8f71b71fce1b 47 ///
WiredHome 5:49dd0c647a40 48 SignalGenDAC(PinName aout = p18, float minV = 0.0, float maxV = 3.3);
WiredHome 2:8f71b71fce1b 49
WiredHome 2:8f71b71fce1b 50 /// Destructor
WiredHome 2:8f71b71fce1b 51 ///
WiredHome 2:8f71b71fce1b 52 ~SignalGenDAC();
WiredHome 2:8f71b71fce1b 53
WiredHome 2:8f71b71fce1b 54 /// Create the waveform in the private memory buffer that is used to DMA to the DAC
WiredHome 2:8f71b71fce1b 55 ///
WiredHome 2:8f71b71fce1b 56 /// @param[in] mode defines the waveform: Sine, Square, Triangle, Sawtooth, User
WiredHome 2:8f71b71fce1b 57 /// @param[in] frequency defines the desired frequency
WiredHome 2:8f71b71fce1b 58 /// @param[in] dutycycle defined the duty cycle of the waveform to be created. The value
WiredHome 2:8f71b71fce1b 59 /// is range limited to 5 to 95 (representing 5 to 95 %).
WiredHome 2:8f71b71fce1b 60 /// @param[in] voltage is the peak-to-peak voltage, and it range limited to 0 to 3.0.
WiredHome 2:8f71b71fce1b 61 /// @param[in] offset is the offset voltage, and is range limited to 0 to 3.0.
WiredHome 2:8f71b71fce1b 62 ///
WiredHome 6:1f48212fbaf9 63 void PrepareWaveform(SG_Waveform mode, float frequency, float dutycycle, float voltage, float offset);
WiredHome 2:8f71b71fce1b 64
WiredHome 2:8f71b71fce1b 65 /// Start the signal, in either a oneshot, or continuous mode.
WiredHome 2:8f71b71fce1b 66 ///
WiredHome 2:8f71b71fce1b 67 /// @param[in] oneShot defaults false, which causes continuous mode.
WiredHome 2:8f71b71fce1b 68 /// When set true, one cycle is produced.
WiredHome 2:8f71b71fce1b 69 ///
WiredHome 2:8f71b71fce1b 70 void Start(bool oneShot = false);
WiredHome 2:8f71b71fce1b 71
WiredHome 2:8f71b71fce1b 72 /// Stop the signal, if it is running.
WiredHome 2:8f71b71fce1b 73 ///
WiredHome 2:8f71b71fce1b 74 void Stop(void);
WiredHome 2:8f71b71fce1b 75
WiredHome 2:8f71b71fce1b 76 /// Determine if the signal is running.
WiredHome 2:8f71b71fce1b 77 ///
WiredHome 2:8f71b71fce1b 78 /// @returns true if the signal is running.
WiredHome 2:8f71b71fce1b 79 ///
WiredHome 2:8f71b71fce1b 80 bool isRunning(void) { return isOn; }
WiredHome 2:8f71b71fce1b 81
WiredHome 2:8f71b71fce1b 82 private:
WiredHome 2:8f71b71fce1b 83 bool isOn; // tracks whether the signal is on or off
WiredHome 2:8f71b71fce1b 84 AnalogOut * aout;
WiredHome 5:49dd0c647a40 85 float frequency; // signal parameters
WiredHome 5:49dd0c647a40 86 float dutycycle;
WiredHome 5:49dd0c647a40 87 float voltage;
WiredHome 5:49dd0c647a40 88 float offset;
WiredHome 2:8f71b71fce1b 89 float minV; // Based on the A/D hardware
WiredHome 2:8f71b71fce1b 90 float maxV; // Based on the A/D hardware
WiredHome 2:8f71b71fce1b 91 /// range limit a value.
WiredHome 2:8f71b71fce1b 92 float rangelimit(float value, float min, float max);
WiredHome 4:10281ddb673d 93 int numSamples; // private container for number of samples
WiredHome 2:8f71b71fce1b 94 };
WiredHome 2:8f71b71fce1b 95
WiredHome 2:8f71b71fce1b 96 #endif // SIGNALGENDAC_H