src/libs/StepperMotor.cpp

   1 /*
   2       This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
   3       Smoothie is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
   4       Smoothie is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   5       You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
   6 */
   7 #include "StepperMotor.h"
   8
   9 #include "Kernel.h"
  10 #include "MRI_Hooks.h"
  11 #include "StepTicker.h"
  12
  13 #include <math.h>
  14
  15 // A StepperMotor represents an actual stepper motor. It is used to generate steps that move the actual motor at a given speed
  16 // TODO : Abstract this into Actuator
  17
  18 StepperMotor::StepperMotor()
  19 {
  20     init();
  21 }
  22
  23 StepperMotor::StepperMotor(Pin &step, Pin &dir, Pin &en) : step_pin(step), dir_pin(dir), en_pin(en)
  24 {
  25     init();
  26     enable(false);
  27     set_high_on_debug(en.port_number, en.pin);
  28 }
  29
  30 void StepperMotor::init()
  31 {
  32     this->moving = false;
  33     this->paused = false;
  34     this->fx_counter = 0;
  35     this->stepped = 0;
  36     this->fx_ticks_per_step = 0;
  37     this->steps_to_move = 0;
  38     this->remove_from_active_list_next_reset = false;
  39     this->is_move_finished = false;
  40     this->signal_step = false;
  41     this->step_signal_hook = new Hook();
  42
  43     steps_per_mm         = 1.0F;
  44     max_rate             = 50.0F;
  45
  46     current_position_steps= 0;
  47     last_milestone_steps = 0;
  48     last_milestone_mm    = 0.0F;
  49 }
  50
  51
  52 // This is called ( see the .h file, we had to put a part of things there for obscure inline reasons ) when a step has to be generated
  53 // we also here check if the move is finished etc ...
  54 void StepperMotor::step()
  55 {
  56     // output to pins 37t
  57     this->step_pin.set( 1 );
  58     this->step_ticker->reset_step_pins = true;
  59
  60     // move counter back 11t
  61     if(this->fx_counter > this->fx_ticks_per_step) {
  62         this->fx_counter -= this->fx_ticks_per_step;
  63     }else{
  64         this->fx_counter= 0; // can't make it less than 0 as it is a uint
  65     }
  66
  67     // we have moved a step 9t
  68     this->stepped++;
  69
  70     // Do we need to signal this step
  71     if( this->stepped == this->signal_step_number && this->signal_step ) {
  72         this->step_signal_hook->call();
  73     }
  74
  75     // keep track of actuators actual position in steps
  76     this->current_position_steps += (this->direction ? -1 : 1);
  77
  78     // Is this move finished ?
  79     if( this->stepped == this->steps_to_move ) {
  80         // Mark it as finished, then StepTicker will call signal_mode_finished()
  81         // This is so we don't call that before all the steps have been generated for this tick()
  82         this->is_move_finished = true;
  83         this->step_ticker->moves_finished = true;
  84     }
  85 }
  86
  87
  88 // If the move is finished, the StepTicker will call this ( because we asked it to in tick() )
  89 void StepperMotor::signal_move_finished()
  90 {
  91     // work is done ! 8t
  92     this->moving = false;
  93     this->steps_to_move = 0;
  94
  95     // signal it to whatever cares 41t 411t
  96     this->end_hook->call();
  97
  98     // We only need to do this if we were not instructed to move
  99     // NOTE this is always true
 100     if( this->moving == false ) {
 101         this->update_exit_tick();
 102     }
 103
 104     this->is_move_finished = false;
 105 }
 106
 107 // This is just a way not to check for ( !this->moving || this->paused || this->fx_ticks_per_step == 0 ) at every tick()
 108 inline void StepperMotor::update_exit_tick()
 109 {
 110     if( !this->moving || this->paused || this->steps_to_move == 0 ) {
 111         // We must exit tick() after setting the pins, no bresenham is done
 112         //this->remove_from_active_list_next_reset = true;
 113         this->step_ticker->remove_motor_from_active_list(this);
 114     } else {
 115         // We must do the bresenham in tick()
 116         // We have to do this or there could be a bug where the removal still happens when it doesn't need to
 117         this->step_ticker->add_motor_to_active_list(this);
 118     }
 119 }
 120
 121 // Instruct the StepperMotor to move a certain number of steps
 122 void StepperMotor::move( bool direction, unsigned int steps, float initial_speed)
 123 {
 124     // We do not set the direction directly, we will set the pin just before the step pin on the next tick
 125     this->dir_pin.set(direction);
 126     this->direction = direction;
 127
 128     // How many steps we have to move until the move is done
 129     this->steps_to_move = steps;
 130
 131     // Zero our tool counters
 132     this->fx_counter = 0;      // Bresenheim counter
 133     this->stepped = 0;
 134
 135     // Do not signal steps until we get instructed to
 136     this->signal_step = false;
 137
 138     // Starting now we are moving
 139     if( steps > 0 ) {
 140         set_speed(initial_speed);
 141         this->moving = true;
 142     } else {
 143         this->moving = false;
 144     }
 145     this->update_exit_tick();
 146 }
 147
 148 // Set the speed at which this steper moves
 149 void StepperMotor::set_speed( float speed )
 150 {
 151     float slowest_speed= ceil(this->step_ticker->frequency/65536.0F);
 152
 153     if(speed < slowest_speed) { // this is the slowest it can be
 154         speed= slowest_speed;
 155     }
 156
 157     // How many steps we must output per second
 158     this->steps_per_second = speed;
 159
 160     // How many ticks ( base steps ) between each actual step at this speed, in fixed point 64 <--- REALLY? I don't think it is at the moment looks like 32bit fixed point
 161     float ticks_per_step = (float)( (float)this->step_ticker->frequency / speed );
 162     float double_fx_ticks_per_step = 65536.0F * ticks_per_step; // isn't this better on a 32bit machine?
 163
 164     // set the new speed
 165     this->fx_ticks_per_step = (uint32_t)( floor(double_fx_ticks_per_step) );
 166 }
 167
 168 // Pause this stepper motor
 169 void StepperMotor::pause()
 170 {
 171     this->paused = true;
 172     this->update_exit_tick();
 173 }
 174
 175 // Unpause this stepper motor
 176 void StepperMotor::unpause()
 177 {
 178     this->paused = false;
 179     this->update_exit_tick();
 180 }
 181
 182
 183 void StepperMotor::change_steps_per_mm(float new_steps)
 184 {
 185     steps_per_mm = new_steps;
 186     last_milestone_steps = lround(last_milestone_mm * steps_per_mm);
 187     current_position_steps = last_milestone_steps;
 188 }
 189
 190 void StepperMotor::change_last_milestone(float new_milestone)
 191 {
 192     last_milestone_mm = new_milestone;
 193     last_milestone_steps = lround(last_milestone_mm * steps_per_mm);
 194     current_position_steps = last_milestone_steps;
 195 }
 196
 197 int  StepperMotor::steps_to_target(float target)
 198 {
 199     int target_steps = lround(target * steps_per_mm);
 200     return target_steps - last_milestone_steps;
 201 }