Ian McCulloch / VNH5019

Library for the VNH5019 Motor Driver, with a helper class for the Pololu Dual VNH5019 Dual Motor Driver Shield http://www.pololu.com/product/2502

Dependents:   VNH5019_second VNH5019_second1

VNH5019.cpp@1:5e8d9ed18f0f, 2014-02-01 (annotated)

Committer:
ianmcc
Date:
Sat Feb 01 14:46:45 2014 +0000
Revision:
1:5e8d9ed18f0f
Parent:
0:5d3ab0ea7f27
Child:
3:2b139675f60d
Refactor into a VNH5019 class to control a single motor, and a helper class for the dual shield.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ianmcc 1:5e8d9ed18f0f 1 #include "VNH5019.h"
ianmcc 0:5d3ab0ea7f27 2
ianmcc 1:5e8d9ed18f0f 3 VNH5019::VNH5019(PinName INA_, PinName INB_, PinName ENDIAG_, PinName CS_, PinName PWM_)
ianmcc 1:5e8d9ed18f0f 4 : INA(INA_),
ianmcc 1:5e8d9ed18f0f 5 INB(INB_),
ianmcc 1:5e8d9ed18f0f 6 ENDIAG(ENDIAG_),
ianmcc 1:5e8d9ed18f0f 7 CS(CS_),
ianmcc 1:5e8d9ed18f0f 8 PWM(PWM_)
ianmcc 0:5d3ab0ea7f27 9 {
ianmcc 0:5d3ab0ea7f27 10 this->init();
ianmcc 0:5d3ab0ea7f27 11 }
ianmcc 0:5d3ab0ea7f27 12
ianmcc 1:5e8d9ed18f0f 13 void VNH5019::init()
ianmcc 0:5d3ab0ea7f27 14 {
ianmcc 1:5e8d9ed18f0f 15 ENDIAG.input();
ianmcc 1:5e8d9ed18f0f 16 ENDIAG.mode(PullUp);
ianmcc 1:5e8d9ed18f0f 17 PWM.period(0.00025); // 4 kHz (valid 0 - 20 kHz)
ianmcc 1:5e8d9ed18f0f 18 PWM.write(0);
ianmcc 1:5e8d9ed18f0f 19 INA = 0;
ianmcc 1:5e8d9ed18f0f 20 INB = 0;
ianmcc 0:5d3ab0ea7f27 21 }
ianmcc 0:5d3ab0ea7f27 22
ianmcc 1:5e8d9ed18f0f 23 void VNH5019::speed(float Speed)
ianmcc 0:5d3ab0ea7f27 24 {
ianmcc 0:5d3ab0ea7f27 25 bool Reverse = 0;
ianmcc 0:5d3ab0ea7f27 26
ianmcc 0:5d3ab0ea7f27 27 if (Speed < 0)
ianmcc 0:5d3ab0ea7f27 28 {
ianmcc 0:5d3ab0ea7f27 29 Speed = -Speed; // Make speed a positive quantity
ianmcc 0:5d3ab0ea7f27 30 Reverse = 1; // Preserve the direction
ianmcc 0:5d3ab0ea7f27 31 }
ianmcc 0:5d3ab0ea7f27 32
ianmcc 0:5d3ab0ea7f27 33 // clamp the speed at maximum
ianmcc 0:5d3ab0ea7f27 34 if (Speed > 1.0)
ianmcc 0:5d3ab0ea7f27 35 Speed = 1.0;
ianmcc 0:5d3ab0ea7f27 36
ianmcc 0:5d3ab0ea7f27 37 if (Speed == 0.0)
ianmcc 0:5d3ab0ea7f27 38 {
ianmcc 1:5e8d9ed18f0f 39 INA = 0;
ianmcc 1:5e8d9ed18f0f 40 INB = 0;
ianmcc 0:5d3ab0ea7f27 41 }
ianmcc 0:5d3ab0ea7f27 42 else
ianmcc 0:5d3ab0ea7f27 43 {
ianmcc 1:5e8d9ed18f0f 44 INA = !Reverse;
ianmcc 1:5e8d9ed18f0f 45 INB = Reverse;
ianmcc 1:5e8d9ed18f0f 46 PWM = Speed;
ianmcc 0:5d3ab0ea7f27 47 }
ianmcc 0:5d3ab0ea7f27 48 }
ianmcc 0:5d3ab0ea7f27 49
ianmcc 1:5e8d9ed18f0f 50 void VNH5019::brake(float Brake)
ianmcc 0:5d3ab0ea7f27 51 {
ianmcc 0:5d3ab0ea7f27 52 // normalize Brake to 0..1
ianmcc 0:5d3ab0ea7f27 53 if (Brake < 0)
ianmcc 1:5e8d9ed18f0f 54 Brake = -Brake;
ianmcc 0:5d3ab0ea7f27 55 if (Brake > 1.0)
ianmcc 0:5d3ab0ea7f27 56 Brake = 1.0;
ianmcc 0:5d3ab0ea7f27 57
ianmcc 1:5e8d9ed18f0f 58 INA = 0;
ianmcc 1:5e8d9ed18f0f 59 INB = 0;
ianmcc 1:5e8d9ed18f0f 60 PWM = Brake;
ianmcc 0:5d3ab0ea7f27 61 }
ianmcc 0:5d3ab0ea7f27 62
ianmcc 1:5e8d9ed18f0f 63 float VNH5019::get_current_mA()
ianmcc 0:5d3ab0ea7f27 64 {
ianmcc 0:5d3ab0ea7f27 65 // Scale is 144mV per A
ianmcc 0:5d3ab0ea7f27 66 // Scale factor is 3.3 / 0.144 = 22.916667
ianmcc 1:5e8d9ed18f0f 67 return CS.read() * 22.916667;
ianmcc 0:5d3ab0ea7f27 68 }
ianmcc 0:5d3ab0ea7f27 69
ianmcc 1:5e8d9ed18f0f 70 bool VNH5019::is_fault()
ianmcc 0:5d3ab0ea7f27 71 {
ianmcc 1:5e8d9ed18f0f 72 return !ENDIAG;
ianmcc 0:5d3ab0ea7f27 73 }
ianmcc 0:5d3ab0ea7f27 74
ianmcc 1:5e8d9ed18f0f 75 void VNH5019::clear_fault()
ianmcc 0:5d3ab0ea7f27 76 {
ianmcc 0:5d3ab0ea7f27 77 // if ENDIAG is high, then there is no fault
ianmcc 1:5e8d9ed18f0f 78 if (ENDIAG.read())
ianmcc 0:5d3ab0ea7f27 79 return;
ianmcc 0:5d3ab0ea7f27 80
ianmcc 0:5d3ab0ea7f27 81 // toggle the inputs
ianmcc 1:5e8d9ed18f0f 82 INA = 0;
ianmcc 1:5e8d9ed18f0f 83 INB = 0;
ianmcc 0:5d3ab0ea7f27 84 wait_us(250);
ianmcc 1:5e8d9ed18f0f 85 INA = 1;
ianmcc 1:5e8d9ed18f0f 86 INB = 1;
ianmcc 0:5d3ab0ea7f27 87 wait_us(250);
ianmcc 0:5d3ab0ea7f27 88
ianmcc 0:5d3ab0ea7f27 89 // pull low all inputs and wait 1600us for t_DEL
ianmcc 1:5e8d9ed18f0f 90 INA = 0;
ianmcc 1:5e8d9ed18f0f 91 INB = 0;
ianmcc 1:5e8d9ed18f0f 92 PWM = 0;
ianmcc 1:5e8d9ed18f0f 93 ENDIAG.output();
ianmcc 1:5e8d9ed18f0f 94 ENDIAG = 0;
ianmcc 0:5d3ab0ea7f27 95 wait_us(1600);
ianmcc 0:5d3ab0ea7f27 96
ianmcc 0:5d3ab0ea7f27 97 // and finally re-enable the motor
ianmcc 1:5e8d9ed18f0f 98 ENDIAG.input();
ianmcc 0:5d3ab0ea7f27 99 }
ianmcc 1:5e8d9ed18f0f 100
ianmcc 1:5e8d9ed18f0f 101 void VNH5019::disable()
ianmcc 0:5d3ab0ea7f27 102 {
ianmcc 1:5e8d9ed18f0f 103 ENDIAG.output();
ianmcc 1:5e8d9ed18f0f 104 ENDIAG.write(0);
ianmcc 0:5d3ab0ea7f27 105 }
ianmcc 0:5d3ab0ea7f27 106
ianmcc 1:5e8d9ed18f0f 107 void VNH5019::enable()
ianmcc 0:5d3ab0ea7f27 108 {
ianmcc 1:5e8d9ed18f0f 109 ENDIAG.input();
ianmcc 0:5d3ab0ea7f27 110 }
ianmcc 0:5d3ab0ea7f27 111
ianmcc 1:5e8d9ed18f0f 112 DualVNH5019MotorShield::DualVNH5019MotorShield()
ianmcc 1:5e8d9ed18f0f 113 : m1(PTD4, PTA4, PTC8, PTB0, PTD5),
ianmcc 1:5e8d9ed18f0f 114 m2(PTC9, PTA13, PTD3, PTB1, PTD0)
ianmcc 0:5d3ab0ea7f27 115 {
ianmcc 0:5d3ab0ea7f27 116 }
ianmcc 0:5d3ab0ea7f27 117
ianmcc 1:5e8d9ed18f0f 118 DualVNH5019MotorShield::DualVNH5019MotorShield(PinName INA1_, PinName INB1_, PinName ENDIAG1_, PinName CS1_, PinName PWM1_,
ianmcc 1:5e8d9ed18f0f 119 PinName INA2_, PinName INB2_, PinName ENDIAG2_, PinName CS2_, PinName PWM2_)
ianmcc 1:5e8d9ed18f0f 120 : m1(INA1_, INB1_, ENDIAG1_, CS1_, PWM1_),
ianmcc 1:5e8d9ed18f0f 121 m2(INA2_, INB2_, ENDIAG2_, CS2_, PWM2_)
ianmcc 0:5d3ab0ea7f27 122 {
ianmcc 0:5d3ab0ea7f27 123 }
ianmcc 1:5e8d9ed18f0f 124
ianmcc 1:5e8d9ed18f0f 125 VNH5019&
ianmcc 1:5e8d9ed18f0f 126 DualVNH5019MotorShield::operator()(int m)
ianmcc 1:5e8d9ed18f0f 127 {
ianmcc 1:5e8d9ed18f0f 128 return m == 1 ? m1 : m2;
ianmcc 1:5e8d9ed18f0f 129 }