Alvaro Cassinelli / Mbed 2 deprecated laserUI

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Dependencies:   mbed

Fork of skinGames_forktest by Alvaro Cassinelli

hardwareIO/lockin.h@14:0fc33a3a7b4b, 2012-04-12 (annotated)

Committer:
mbedalvaro
Date:
Thu Apr 12 13:02:59 2012 +0000
Revision:
14:0fc33a3a7b4b
Parent:
10:6f8e48dca1bd
Child:
23:bf666fcc61bc
checking old version, need to branch

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbedalvaro 0:345b3bc7a0ea 1 #ifndef MBED_LOCKIN_H
mbedalvaro 0:345b3bc7a0ea 2 #define MBED_LOCKIN_H
mbedalvaro 0:345b3bc7a0ea 3
mbedalvaro 0:345b3bc7a0ea 4 #include "mbed.h"
mbedalvaro 0:345b3bc7a0ea 5 #include "adc.h"
mbedalvaro 0:345b3bc7a0ea 6
mbedalvaro 0:345b3bc7a0ea 7 #define MBEDFREQUENCY 96000 //frequency of the mBed in KHz
mbedalvaro 0:345b3bc7a0ea 8
mbedalvaro 0:345b3bc7a0ea 9 //#define I_Volts_SAT 5 // this is 5V (the saturation voltage for the APD+LockIn+ADC, being it the arduino (when in normal mode) or the SPI. This saturation voltage could be different for each mode!?
mbedalvaro 0:345b3bc7a0ea 10
mbedalvaro 0:345b3bc7a0ea 11 #define LOCKIN_ADC_PIN p18 //ADC pin : connect to lockin output
mbedalvaro 0:345b3bc7a0ea 12 #define LOCKIN_LASER_PIN p22 //PWM pin : connect to laser input
mbedalvaro 0:345b3bc7a0ea 13 #define LOCKIN_REF_PIN p25 //PWM pin : connect to lockin input
mbedalvaro 0:345b3bc7a0ea 14 // p21 to p25 are used by the PWM timers even if only 2 pin are connected to the circuit
mbedalvaro 0:345b3bc7a0ea 15
mbedalvaro 0:345b3bc7a0ea 16 #define BUFFER_SIZE 15
mbedalvaro 0:345b3bc7a0ea 17 #define BUFFER_SIZE_MEDIAN 5
mbedalvaro 0:345b3bc7a0ea 18 #define DELAY_BUFFER_MEDIAN 0
mbedalvaro 0:345b3bc7a0ea 19
mbedalvaro 0:345b3bc7a0ea 20
mbedalvaro 0:345b3bc7a0ea 21 class Lockin {
mbedalvaro 0:345b3bc7a0ea 22 public:
mbedalvaro 0:345b3bc7a0ea 23 // default constructor (untouched!)
mbedalvaro 0:345b3bc7a0ea 24 // Lockin();
mbedalvaro 0:345b3bc7a0ea 25
mbedalvaro 0:345b3bc7a0ea 26 // initialization of object modes (could have parameters):
mbedalvaro 0:345b3bc7a0ea 27 void init();
mbedalvaro 0:345b3bc7a0ea 28
mbedalvaro 0:345b3bc7a0ea 29 void initPWM(); //setup the laser and reference signal used by the lockin
mbedalvaro 0:345b3bc7a0ea 30 void setPWMFrequency(float freq); //change the shared period of the pwm signals
mbedalvaro 0:345b3bc7a0ea 31 void setLaserPhaseShift(float phaseShift); //change the phase shift of the laser (from 0 to 1)
mbedalvaro 0:345b3bc7a0ea 32 void setLockinPhaseShift(float phaseShift); //change the phase shift of the lock-in (from 0 to 1)
mbedalvaro 0:345b3bc7a0ea 33 //future works:
mbedalvaro 0:345b3bc7a0ea 34 //add function to change frequency or offset with a potentiometer for exemple
mbedalvaro 0:345b3bc7a0ea 35 //or scan the best frequency...
mbedalvaro 0:345b3bc7a0ea 36
mbedalvaro 0:345b3bc7a0ea 37 void setLaserPower(bool power); //change PWM settings to turn on/off the laser
mbedalvaro 0:345b3bc7a0ea 38
mbedalvaro 0:345b3bc7a0ea 39
mbedalvaro 10:6f8e48dca1bd 40 unsigned short getSmoothValue(); //return the average of the value stored on the buffer
mbedalvaro 10:6f8e48dca1bd 41 unsigned short getLastValue(); //return the last conversion of the ADC
mbedalvaro 10:6f8e48dca1bd 42 unsigned short getMedianValue(); //return the median value of the buffer
mbedalvaro 0:345b3bc7a0ea 43 //it is just a begining; we can add more complex method for denoising for exemple
mbedalvaro 0:345b3bc7a0ea 44 //maybe, needs function to start and stop the lockin
mbedalvaro 0:345b3bc7a0ea 45
mbedalvaro 0:345b3bc7a0ea 46 void clearBuffer();
mbedalvaro 0:345b3bc7a0ea 47
mbedalvaro 0:345b3bc7a0ea 48 //can be private
mbedalvaro 0:345b3bc7a0ea 49 //void catchInterupt(uint32_t value);
mbedalvaro 0:345b3bc7a0ea 50
mbedalvaro 0:345b3bc7a0ea 51 //variables
mbedalvaro 10:6f8e48dca1bd 52 unsigned short buffer[BUFFER_SIZE]; // does not need to be a float - in fact values are from 0 to 4096 (i.e.,
mbedalvaro 1:a4050fee11f7 53 //unsigned short int buffer[BUFFER_SIZE]; // this is two bytes (0 to 65535)
mbedalvaro 14:0fc33a3a7b4b 54 unsigned short orderedBuffer[BUFFER_SIZE_MEDIAN]; // for computation of the MEDIAN value
mbedalvaro 0:345b3bc7a0ea 55 int buffer_pos;
mbedalvaro 0:345b3bc7a0ea 56
mbedalvaro 0:345b3bc7a0ea 57 float refFrequency; // frequency of sensing laser and lock-in (in KHz)
mbedalvaro 0:345b3bc7a0ea 58 //Phase shift of the pwm signals (from 0 to 1):
mbedalvaro 0:345b3bc7a0ea 59 //it corresponds to a percentage of the half of a period
mbedalvaro 0:345b3bc7a0ea 60 //(no phase shift ==> 0% / 90deg phase shift ==> 100%)
mbedalvaro 0:345b3bc7a0ea 61 float phaseShiftLaser; // phase shift of the sensing laser
mbedalvaro 0:345b3bc7a0ea 62 float phaseShiftLockin; // phase shift of the lock-in reference
mbedalvaro 0:345b3bc7a0ea 63
mbedalvaro 0:345b3bc7a0ea 64 int refFreq; //frequency of the lockin
mbedalvaro 0:345b3bc7a0ea 65 int offsetRef; //offset between the laser signal and the lockin reference signal
mbedalvaro 0:345b3bc7a0ea 66 int halfRefFreq;
mbedalvaro 0:345b3bc7a0ea 67
mbedalvaro 0:345b3bc7a0ea 68 private:
mbedalvaro 0:345b3bc7a0ea 69 // PWM match register value are saved as private
mbedalvaro 0:345b3bc7a0ea 70 // to avoid computation when turn on/off for exemple
mbedalvaro 0:345b3bc7a0ea 71 int _currentMR[6];
mbedalvaro 0:345b3bc7a0ea 72
mbedalvaro 0:345b3bc7a0ea 73
mbedalvaro 0:345b3bc7a0ea 74 };
mbedalvaro 0:345b3bc7a0ea 75
mbedalvaro 0:345b3bc7a0ea 76 extern Lockin lockin;
mbedalvaro 0:345b3bc7a0ea 77
mbedalvaro 0:345b3bc7a0ea 78 #endif