diff options
| author | Jesse Morgan <jesse@jesterpm.net> | 2011-10-20 22:16:19 -0700 |
|---|---|---|
| committer | Jesse Morgan <jesse@jesterpm.net> | 2011-10-20 22:16:19 -0700 |
| commit | fc944ff979dbbd49a57722fe2d1d2acf47312eb4 (patch) | |
| tree | 38cc3a5c5c8f24f55068fc4ffa73d018169fc2df /libraries/Stepper/Stepper.cpp | |
Inital commit... halfway through the project
Diffstat (limited to 'libraries/Stepper/Stepper.cpp')
| -rw-r--r-- | libraries/Stepper/Stepper.cpp | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/libraries/Stepper/Stepper.cpp b/libraries/Stepper/Stepper.cpp new file mode 100644 index 0000000..d5fa129 --- /dev/null +++ b/libraries/Stepper/Stepper.cpp @@ -0,0 +1,220 @@ +/*
+ Stepper.cpp - - Stepper library for Wiring/Arduino - Version 0.4
+
+ Original library (0.1) by Tom Igoe.
+ Two-wire modifications (0.2) by Sebastian Gassner
+ Combination version (0.3) by Tom Igoe and David Mellis
+ Bug fix for four-wire (0.4) by Tom Igoe, bug fix from Noah Shibley
+
+ Drives a unipolar or bipolar stepper motor using 2 wires or 4 wires
+
+ When wiring multiple stepper motors to a microcontroller,
+ you quickly run out of output pins, with each motor requiring 4 connections.
+
+ By making use of the fact that at any time two of the four motor
+ coils are the inverse of the other two, the number of
+ control connections can be reduced from 4 to 2.
+
+ A slightly modified circuit around a Darlington transistor array or an L293 H-bridge
+ connects to only 2 microcontroler pins, inverts the signals received,
+ and delivers the 4 (2 plus 2 inverted ones) output signals required
+ for driving a stepper motor.
+
+ The sequence of control signals for 4 control wires is as follows:
+
+ Step C0 C1 C2 C3
+ 1 1 0 1 0
+ 2 0 1 1 0
+ 3 0 1 0 1
+ 4 1 0 0 1
+
+ The sequence of controls signals for 2 control wires is as follows
+ (columns C1 and C2 from above):
+
+ Step C0 C1
+ 1 0 1
+ 2 1 1
+ 3 1 0
+ 4 0 0
+
+ The circuits can be found at
+
+http://www.arduino.cc/en/Tutorial/Stepper
+
+
+ */
+
+
+#include "WProgram.h"
+#include "Stepper.h"
+
+/*
+ * two-wire constructor.
+ * Sets which wires should control the motor.
+ */
+Stepper::Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2)
+{
+ this->step_number = 0; // which step the motor is on
+ this->speed = 0; // the motor speed, in revolutions per minute
+ this->direction = 0; // motor direction
+ this->last_step_time = 0; // time stamp in ms of the last step taken
+ this->number_of_steps = number_of_steps; // total number of steps for this motor
+
+ // Arduino pins for the motor control connection:
+ this->motor_pin_1 = motor_pin_1;
+ this->motor_pin_2 = motor_pin_2;
+
+ // setup the pins on the microcontroller:
+ pinMode(this->motor_pin_1, OUTPUT);
+ pinMode(this->motor_pin_2, OUTPUT);
+
+ // When there are only 2 pins, set the other two to 0:
+ this->motor_pin_3 = 0;
+ this->motor_pin_4 = 0;
+
+ // pin_count is used by the stepMotor() method:
+ this->pin_count = 2;
+}
+
+
+/*
+ * constructor for four-pin version
+ * Sets which wires should control the motor.
+ */
+
+Stepper::Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4)
+{
+ this->step_number = 0; // which step the motor is on
+ this->speed = 0; // the motor speed, in revolutions per minute
+ this->direction = 0; // motor direction
+ this->last_step_time = 0; // time stamp in ms of the last step taken
+ this->number_of_steps = number_of_steps; // total number of steps for this motor
+
+ // Arduino pins for the motor control connection:
+ this->motor_pin_1 = motor_pin_1;
+ this->motor_pin_2 = motor_pin_2;
+ this->motor_pin_3 = motor_pin_3;
+ this->motor_pin_4 = motor_pin_4;
+
+ // setup the pins on the microcontroller:
+ pinMode(this->motor_pin_1, OUTPUT);
+ pinMode(this->motor_pin_2, OUTPUT);
+ pinMode(this->motor_pin_3, OUTPUT);
+ pinMode(this->motor_pin_4, OUTPUT);
+
+ // pin_count is used by the stepMotor() method:
+ this->pin_count = 4;
+}
+
+/*
+ Sets the speed in revs per minute
+
+*/
+void Stepper::setSpeed(long whatSpeed)
+{
+ this->step_delay = 60L * 1000L / this->number_of_steps / whatSpeed;
+}
+
+/*
+ Moves the motor steps_to_move steps. If the number is negative,
+ the motor moves in the reverse direction.
+ */
+void Stepper::step(int steps_to_move)
+{
+ int steps_left = abs(steps_to_move); // how many steps to take
+
+ // determine direction based on whether steps_to_mode is + or -:
+ if (steps_to_move > 0) {this->direction = 1;}
+ if (steps_to_move < 0) {this->direction = 0;}
+
+
+ // decrement the number of steps, moving one step each time:
+ while(steps_left > 0) {
+ // move only if the appropriate delay has passed:
+ if (millis() - this->last_step_time >= this->step_delay) {
+ // get the timeStamp of when you stepped:
+ this->last_step_time = millis();
+ // increment or decrement the step number,
+ // depending on direction:
+ if (this->direction == 1) {
+ this->step_number++;
+ if (this->step_number == this->number_of_steps) {
+ this->step_number = 0;
+ }
+ }
+ else {
+ if (this->step_number == 0) {
+ this->step_number = this->number_of_steps;
+ }
+ this->step_number--;
+ }
+ // decrement the steps left:
+ steps_left--;
+ // step the motor to step number 0, 1, 2, or 3:
+ stepMotor(this->step_number % 4);
+ }
+ }
+}
+
+/*
+ * Moves the motor forward or backwards.
+ */
+void Stepper::stepMotor(int thisStep)
+{
+ if (this->pin_count == 2) {
+ switch (thisStep) {
+ case 0: /* 01 */
+ digitalWrite(motor_pin_1, LOW);
+ digitalWrite(motor_pin_2, HIGH);
+ break;
+ case 1: /* 11 */
+ digitalWrite(motor_pin_1, HIGH);
+ digitalWrite(motor_pin_2, HIGH);
+ break;
+ case 2: /* 10 */
+ digitalWrite(motor_pin_1, HIGH);
+ digitalWrite(motor_pin_2, LOW);
+ break;
+ case 3: /* 00 */
+ digitalWrite(motor_pin_1, LOW);
+ digitalWrite(motor_pin_2, LOW);
+ break;
+ }
+ }
+ if (this->pin_count == 4) {
+ switch (thisStep) {
+ case 0: // 1010
+ digitalWrite(motor_pin_1, HIGH);
+ digitalWrite(motor_pin_2, LOW);
+ digitalWrite(motor_pin_3, HIGH);
+ digitalWrite(motor_pin_4, LOW);
+ break;
+ case 1: // 0110
+ digitalWrite(motor_pin_1, LOW);
+ digitalWrite(motor_pin_2, HIGH);
+ digitalWrite(motor_pin_3, HIGH);
+ digitalWrite(motor_pin_4, LOW);
+ break;
+ case 2: //0101
+ digitalWrite(motor_pin_1, LOW);
+ digitalWrite(motor_pin_2, HIGH);
+ digitalWrite(motor_pin_3, LOW);
+ digitalWrite(motor_pin_4, HIGH);
+ break;
+ case 3: //1001
+ digitalWrite(motor_pin_1, HIGH);
+ digitalWrite(motor_pin_2, LOW);
+ digitalWrite(motor_pin_3, LOW);
+ digitalWrite(motor_pin_4, HIGH);
+ break;
+ }
+ }
+}
+
+/*
+ version() returns the version of the library:
+*/
+int Stepper::version(void)
+{
+ return 4;
+}
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