1 | /*
|
---|
2 | Stepper.cpp - - Stepper library for Wiring/Arduino - Version 0.4
|
---|
3 |
|
---|
4 | Original library (0.1) by Tom Igoe.
|
---|
5 | Two-wire modifications (0.2) by Sebastian Gassner
|
---|
6 | Combination version (0.3) by Tom Igoe and David Mellis
|
---|
7 | Bug fix for four-wire (0.4) by Tom Igoe, bug fix from Noah Shibley
|
---|
8 |
|
---|
9 | Drives a unipolar or bipolar stepper motor using 2 wires or 4 wires
|
---|
10 |
|
---|
11 | When wiring multiple stepper motors to a microcontroller,
|
---|
12 | you quickly run out of output pins, with each motor requiring 4 connections.
|
---|
13 |
|
---|
14 | By making use of the fact that at any time two of the four motor
|
---|
15 | coils are the inverse of the other two, the number of
|
---|
16 | control connections can be reduced from 4 to 2.
|
---|
17 |
|
---|
18 | A slightly modified circuit around a Darlington transistor array or an L293 H-bridge
|
---|
19 | connects to only 2 microcontroler pins, inverts the signals received,
|
---|
20 | and delivers the 4 (2 plus 2 inverted ones) output signals required
|
---|
21 | for driving a stepper motor.
|
---|
22 |
|
---|
23 | The sequence of control signals for 4 control wires is as follows:
|
---|
24 |
|
---|
25 | Step C0 C1 C2 C3
|
---|
26 | 1 1 0 1 0
|
---|
27 | 2 0 1 1 0
|
---|
28 | 3 0 1 0 1
|
---|
29 | 4 1 0 0 1
|
---|
30 |
|
---|
31 | The sequence of controls signals for 2 control wires is as follows
|
---|
32 | (columns C1 and C2 from above):
|
---|
33 |
|
---|
34 | Step C0 C1
|
---|
35 | 1 0 1
|
---|
36 | 2 1 1
|
---|
37 | 3 1 0
|
---|
38 | 4 0 0
|
---|
39 |
|
---|
40 | The circuits can be found at
|
---|
41 |
|
---|
42 | http://www.arduino.cc/en/Tutorial/Stepper
|
---|
43 |
|
---|
44 |
|
---|
45 | */
|
---|
46 |
|
---|
47 |
|
---|
48 | #include "Arduino.h"
|
---|
49 | #include "Stepper.h"
|
---|
50 |
|
---|
51 | /*
|
---|
52 | * two-wire constructor.
|
---|
53 | * Sets which wires should control the motor.
|
---|
54 | */
|
---|
55 | Stepper::Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2)
|
---|
56 | {
|
---|
57 | this->step_number = 0; // which step the motor is on
|
---|
58 | this->speed = 0; // the motor speed, in revolutions per minute
|
---|
59 | this->direction = 0; // motor direction
|
---|
60 | this->last_step_time = 0; // time stamp in ms of the last step taken
|
---|
61 | this->number_of_steps = number_of_steps; // total number of steps for this motor
|
---|
62 |
|
---|
63 | // Arduino pins for the motor control connection:
|
---|
64 | this->motor_pin_1 = motor_pin_1;
|
---|
65 | this->motor_pin_2 = motor_pin_2;
|
---|
66 |
|
---|
67 | // setup the pins on the microcontroller:
|
---|
68 | pinMode(this->motor_pin_1, OUTPUT);
|
---|
69 | pinMode(this->motor_pin_2, OUTPUT);
|
---|
70 |
|
---|
71 | // When there are only 2 pins, set the other two to 0:
|
---|
72 | this->motor_pin_3 = 0;
|
---|
73 | this->motor_pin_4 = 0;
|
---|
74 |
|
---|
75 | // pin_count is used by the stepMotor() method:
|
---|
76 | this->pin_count = 2;
|
---|
77 | }
|
---|
78 |
|
---|
79 |
|
---|
80 | /*
|
---|
81 | * constructor for four-pin version
|
---|
82 | * Sets which wires should control the motor.
|
---|
83 | */
|
---|
84 |
|
---|
85 | Stepper::Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4)
|
---|
86 | {
|
---|
87 | this->step_number = 0; // which step the motor is on
|
---|
88 | this->speed = 0; // the motor speed, in revolutions per minute
|
---|
89 | this->direction = 0; // motor direction
|
---|
90 | this->last_step_time = 0; // time stamp in ms of the last step taken
|
---|
91 | this->number_of_steps = number_of_steps; // total number of steps for this motor
|
---|
92 |
|
---|
93 | // Arduino pins for the motor control connection:
|
---|
94 | this->motor_pin_1 = motor_pin_1;
|
---|
95 | this->motor_pin_2 = motor_pin_2;
|
---|
96 | this->motor_pin_3 = motor_pin_3;
|
---|
97 | this->motor_pin_4 = motor_pin_4;
|
---|
98 |
|
---|
99 | // setup the pins on the microcontroller:
|
---|
100 | pinMode(this->motor_pin_1, OUTPUT);
|
---|
101 | pinMode(this->motor_pin_2, OUTPUT);
|
---|
102 | pinMode(this->motor_pin_3, OUTPUT);
|
---|
103 | pinMode(this->motor_pin_4, OUTPUT);
|
---|
104 |
|
---|
105 | // pin_count is used by the stepMotor() method:
|
---|
106 | this->pin_count = 4;
|
---|
107 | }
|
---|
108 |
|
---|
109 | /*
|
---|
110 | Sets the speed in revs per minute
|
---|
111 |
|
---|
112 | */
|
---|
113 | void Stepper::setSpeed(long whatSpeed)
|
---|
114 | {
|
---|
115 | this->step_delay = 60L * 1000L / this->number_of_steps / whatSpeed;
|
---|
116 | }
|
---|
117 |
|
---|
118 | /*
|
---|
119 | Moves the motor steps_to_move steps. If the number is negative,
|
---|
120 | the motor moves in the reverse direction.
|
---|
121 | */
|
---|
122 | void Stepper::step(int steps_to_move)
|
---|
123 | {
|
---|
124 | int steps_left = abs(steps_to_move); // how many steps to take
|
---|
125 |
|
---|
126 | // determine direction based on whether steps_to_mode is + or -:
|
---|
127 | if (steps_to_move > 0) {this->direction = 1;}
|
---|
128 | if (steps_to_move < 0) {this->direction = 0;}
|
---|
129 |
|
---|
130 |
|
---|
131 | // decrement the number of steps, moving one step each time:
|
---|
132 | while(steps_left > 0) {
|
---|
133 | // move only if the appropriate delay has passed:
|
---|
134 | if (millis() - this->last_step_time >= this->step_delay) {
|
---|
135 | // get the timeStamp of when you stepped:
|
---|
136 | this->last_step_time = millis();
|
---|
137 | // increment or decrement the step number,
|
---|
138 | // depending on direction:
|
---|
139 | if (this->direction == 1) {
|
---|
140 | this->step_number++;
|
---|
141 | if (this->step_number == this->number_of_steps) {
|
---|
142 | this->step_number = 0;
|
---|
143 | }
|
---|
144 | }
|
---|
145 | else {
|
---|
146 | if (this->step_number == 0) {
|
---|
147 | this->step_number = this->number_of_steps;
|
---|
148 | }
|
---|
149 | this->step_number--;
|
---|
150 | }
|
---|
151 | // decrement the steps left:
|
---|
152 | steps_left--;
|
---|
153 | // step the motor to step number 0, 1, 2, or 3:
|
---|
154 | stepMotor(this->step_number % 4);
|
---|
155 | }
|
---|
156 | }
|
---|
157 | }
|
---|
158 |
|
---|
159 | /*
|
---|
160 | * Moves the motor forward or backwards.
|
---|
161 | */
|
---|
162 | void Stepper::stepMotor(int thisStep)
|
---|
163 | {
|
---|
164 | if (this->pin_count == 2) {
|
---|
165 | switch (thisStep) {
|
---|
166 | case 0: /* 01 */
|
---|
167 | digitalWrite(motor_pin_1, LOW);
|
---|
168 | digitalWrite(motor_pin_2, HIGH);
|
---|
169 | break;
|
---|
170 | case 1: /* 11 */
|
---|
171 | digitalWrite(motor_pin_1, HIGH);
|
---|
172 | digitalWrite(motor_pin_2, HIGH);
|
---|
173 | break;
|
---|
174 | case 2: /* 10 */
|
---|
175 | digitalWrite(motor_pin_1, HIGH);
|
---|
176 | digitalWrite(motor_pin_2, LOW);
|
---|
177 | break;
|
---|
178 | case 3: /* 00 */
|
---|
179 | digitalWrite(motor_pin_1, LOW);
|
---|
180 | digitalWrite(motor_pin_2, LOW);
|
---|
181 | break;
|
---|
182 | }
|
---|
183 | }
|
---|
184 | if (this->pin_count == 4) {
|
---|
185 | switch (thisStep) {
|
---|
186 | case 0: // 1010
|
---|
187 | digitalWrite(motor_pin_1, HIGH);
|
---|
188 | digitalWrite(motor_pin_2, LOW);
|
---|
189 | digitalWrite(motor_pin_3, HIGH);
|
---|
190 | digitalWrite(motor_pin_4, LOW);
|
---|
191 | break;
|
---|
192 | case 1: // 0110
|
---|
193 | digitalWrite(motor_pin_1, LOW);
|
---|
194 | digitalWrite(motor_pin_2, HIGH);
|
---|
195 | digitalWrite(motor_pin_3, HIGH);
|
---|
196 | digitalWrite(motor_pin_4, LOW);
|
---|
197 | break;
|
---|
198 | case 2: //0101
|
---|
199 | digitalWrite(motor_pin_1, LOW);
|
---|
200 | digitalWrite(motor_pin_2, HIGH);
|
---|
201 | digitalWrite(motor_pin_3, LOW);
|
---|
202 | digitalWrite(motor_pin_4, HIGH);
|
---|
203 | break;
|
---|
204 | case 3: //1001
|
---|
205 | digitalWrite(motor_pin_1, HIGH);
|
---|
206 | digitalWrite(motor_pin_2, LOW);
|
---|
207 | digitalWrite(motor_pin_3, LOW);
|
---|
208 | digitalWrite(motor_pin_4, HIGH);
|
---|
209 | break;
|
---|
210 | }
|
---|
211 | }
|
---|
212 | }
|
---|
213 |
|
---|
214 | /*
|
---|
215 | version() returns the version of the library:
|
---|
216 | */
|
---|
217 | int Stepper::version(void)
|
---|
218 | {
|
---|
219 | return 4;
|
---|
220 | }
|
---|