diff options
Diffstat (limited to 'core/libraries/Stepper/Stepper.cpp')
| -rw-r--r-- | core/libraries/Stepper/Stepper.cpp | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/core/libraries/Stepper/Stepper.cpp b/core/libraries/Stepper/Stepper.cpp new file mode 100644 index 0000000..b10f94c --- /dev/null +++ b/core/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) { + // step the motor to step number 0, 1, 2, or 3: + stepMotor(this->step_number % 4); + // 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--; + } + } +} + +/* + * 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; +} |