Carter Sharer / Joystick_skeleton

ESE519 blank Joystick class

Dependents:   ESE519_Lab6_part1_skeleton

Fork of Joystick_skelleton by Carter Sharer

Joystick.cpp@0:46523bf02e61, 2016-10-18 (annotated)

Committer:
csharer
Date:
Tue Oct 18 20:26:41 2016 +0000
Revision:
0:46523bf02e61
Child:
1:c42a77267f7b
commented

Who changed what in which revision?

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csharer 0:46523bf02e61 1 #include "Joystick.h"
csharer 0:46523bf02e61 2 #include "mbed.h"
csharer 0:46523bf02e61 3
csharer 0:46523bf02e61 4 //Member function definitions including constructor
csharer 0:46523bf02e61 5 Joystick::Joystick(PinName pinA, PinName pinB) : horiz(pinA), vert(pinB) {
csharer 0:46523bf02e61 6 //Wait 1 second for voltage to settle
csharer 0:46523bf02e61 7 wait(1);
csharer 0:46523bf02e61 8
csharer 0:46523bf02e61 9 //Set Raw Center Values, this is where the joystick sits naturaly
csharer 0:46523bf02e61 10 raw_hc = (horiz.read() + horiz.read() + horiz.read() + horiz.read() + horiz.read()) / 5.0;
csharer 0:46523bf02e61 11 raw_vc = (vert.read() + vert.read() + vert.read() + vert.read() + vert.read()) / 5.0;
csharer 0:46523bf02e61 12
csharer 0:46523bf02e61 13 //Initalize the Rax Max to some value less then then real max value.
csharer 0:46523bf02e61 14 //We dont know what the max value will be until we read it.
csharer 0:46523bf02e61 15 //But we can assume it will be greater then 0.8 (center + 0.3)
csharer 0:46523bf02e61 16 //Now do the same for the the Raw Min
csharer 0:46523bf02e61 17 float delta = 0.3;
csharer 0:46523bf02e61 18 rawMinH = raw_hc - delta; rawMaxH = raw_hc + delta;
csharer 0:46523bf02e61 19 rawMinV = raw_hc - delta; rawMaxV = raw_hc + delta;
csharer 0:46523bf02e61 20 }
csharer 0:46523bf02e61 21
csharer 0:46523bf02e61 22 //Returns the scaled vertial value of joystick
csharer 0:46523bf02e61 23 float Joystick::horizontal(void) {
csharer 0:46523bf02e61 24 //Get average val (5 samples)
csharer 0:46523bf02e61 25 float avg = (horiz.read() + horiz.read() + horiz.read() + horiz.read() + horiz.read()) / 5.0;
csharer 0:46523bf02e61 26
csharer 0:46523bf02e61 27 //Watch for Max and Min Values if we see a new max/min update Raw Max/Min
csharer 0:46523bf02e61 28 if(avg > rawMaxH)
csharer 0:46523bf02e61 29 rawMaxH = avg;
csharer 0:46523bf02e61 30 if(avg < rawMinH)
csharer 0:46523bf02e61 31 rawMinH = avg;
csharer 0:46523bf02e61 32
csharer 0:46523bf02e61 33
csharer 0:46523bf02e61 34 //Here we will calculate the total range (Travel) of the joystick
csharer 0:46523bf02e61 35 //using the rawMax/rawMin values we have seen thus far
csharer 0:46523bf02e61 36 //Calculate the range from [center, max] and [center, min]
csharer 0:46523bf02e61 37 float range_pos = rawMaxH - raw_hc;
csharer 0:46523bf02e61 38 float range_neg = raw_hc - rawMinH;
csharer 0:46523bf02e61 39
csharer 0:46523bf02e61 40 //Here we will calculate how much our current reading is in one
csharer 0:46523bf02e61 41 //of the ranges to get a percentage
csharer 0:46523bf02e61 42 //Then we can scale this by multiplying it by our scale (_max/_min)
csharer 0:46523bf02e61 43 float val;
csharer 0:46523bf02e61 44 if(avg >= raw_hc)
csharer 0:46523bf02e61 45 val = ((avg - raw_hc) / range_pos) * _max; // percent to max * max
csharer 0:46523bf02e61 46 else
csharer 0:46523bf02e61 47 val = ((raw_hc - avg) / range_neg) * _min; //percent to min * min
csharer 0:46523bf02e61 48
csharer 0:46523bf02e61 49
csharer 0:46523bf02e61 50 //Here we will apply a dead zone
csharer 0:46523bf02e61 51 if((val <= DEAD_ZONE/2) && (val >= -DEAD_ZONE/2)) {
csharer 0:46523bf02e61 52 return 0;
csharer 0:46523bf02e61 53 }
csharer 0:46523bf02e61 54 else if(val > DEAD_ZONE/2) {//posotive vals
csharer 0:46523bf02e61 55 return val - DEAD_ZONE/2;
csharer 0:46523bf02e61 56 }
csharer 0:46523bf02e61 57 else { //negative vals
csharer 0:46523bf02e61 58 return val + DEAD_ZONE/2;
csharer 0:46523bf02e61 59 }
csharer 0:46523bf02e61 60 }
csharer 0:46523bf02e61 61
csharer 0:46523bf02e61 62 //Returns the scaled horizontal value of joystick
csharer 0:46523bf02e61 63 float Joystick::vertical(void) {
csharer 0:46523bf02e61 64 //Get average value
csharer 0:46523bf02e61 65 float avg = (vert.read() + vert.read() + vert.read() + vert.read() + vert.read()) / 5.0;
csharer 0:46523bf02e61 66
csharer 0:46523bf02e61 67 //Watch for Max and Min Values
csharer 0:46523bf02e61 68 if(avg > rawMaxV)
csharer 0:46523bf02e61 69 rawMaxV = avg;
csharer 0:46523bf02e61 70 if(avg < rawMinV)
csharer 0:46523bf02e61 71 rawMinV = avg;
csharer 0:46523bf02e61 72
csharer 0:46523bf02e61 73 //Calculate Range (Total Travel of joystick)
csharer 0:46523bf02e61 74 float range_pos = rawMaxV - raw_vc;
csharer 0:46523bf02e61 75 float range_neg = raw_vc - rawMinV;
csharer 0:46523bf02e61 76
csharer 0:46523bf02e61 77 float val;
csharer 0:46523bf02e61 78 if(avg >= raw_vc) //find scaled pot value
csharer 0:46523bf02e61 79 val = (((avg - raw_vc) / range_pos) * _max);
csharer 0:46523bf02e61 80 else
csharer 0:46523bf02e61 81 val = (((raw_vc - avg) / range_neg) * _min);
csharer 0:46523bf02e61 82
csharer 0:46523bf02e61 83 //If val is in dead zone range return 0
csharer 0:46523bf02e61 84 if((val <= DEAD_ZONE/2) && (val >= -DEAD_ZONE/2)) {
csharer 0:46523bf02e61 85 return 0;
csharer 0:46523bf02e61 86 }
csharer 0:46523bf02e61 87 //Else return val minus dead zone / 2
csharer 0:46523bf02e61 88 else if(val > DEAD_ZONE/2) {//posotive vals
csharer 0:46523bf02e61 89 return val - DEAD_ZONE/2;
csharer 0:46523bf02e61 90 }
csharer 0:46523bf02e61 91 else { //negative vals
csharer 0:46523bf02e61 92 return val + DEAD_ZONE/2;
csharer 0:46523bf02e61 93 }
csharer 0:46523bf02e61 94 }
csharer 0:46523bf02e61 95
csharer 0:46523bf02e61 96 //Set the Min and Max Values of joystick ex: -100, +100
csharer 0:46523bf02e61 97 void Joystick::setScale(float min, float max) {
csharer 0:46523bf02e61 98 _min = min;
csharer 0:46523bf02e61 99 _max = max;
csharer 0:46523bf02e61 100 }