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/>.
7 #include "StepperMotor.h"
10 #include "MRI_Hooks.h"
11 #include "StepTicker.h"
15 // in steps/sec the default minimum speed (was 20steps/sec hardcoded)
16 float StepperMotor::default_minimum_actuator_rate
= 20.0F
;
18 // A StepperMotor represents an actual stepper motor. It is used to generate steps that move the actual motor at a given speed
20 StepperMotor::StepperMotor()
25 StepperMotor::StepperMotor(Pin
&step
, Pin
&dir
, Pin
&en
) : step_pin(step
), dir_pin(dir
), en_pin(en
)
29 set_high_on_debug(en
.port_number
, en
.pin
);
32 StepperMotor::~StepperMotor()
36 void StepperMotor::init()
38 // register this motor with the step ticker, and get its index in that array and bit position
39 this->index
= THEKERNEL
->step_ticker
->register_motor(this);
42 this->fx_ticks_per_step
= 0xFFFFF000UL
; // some big number so we don't start stepping before it is set
44 this->steps_to_move
= 0;
45 this->is_move_finished
= false;
46 this->last_step_tick_valid
= false;
47 this->last_step_tick
= 0;
51 minimum_step_rate
= default_minimum_actuator_rate
;
53 last_milestone_steps
= 0;
54 last_milestone_mm
= 0.0F
;
55 current_position_steps
= 0;
60 // 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
61 // we also here check if the move is finished etc ..
62 // This is in highest priority interrupt so cannot be pre-empted
63 void StepperMotor::step()
65 // ignore if we are still processing the end of a block
66 if(this->is_move_finished
) return;
69 this->step_pin
.set( 1 );
71 // move counter back 11t
72 this->fx_counter
-= this->fx_ticks_per_step
;
74 // we have moved a step 9t
77 // keep track of actuators actual position in steps
78 this->current_position_steps
+= (this->direction
? -1 : 1);
80 // we may need to callback on a specific step, usually used to synchronize deceleration timer
81 if(this->signal_step
!= 0 && this->stepped
== this->signal_step
) {
82 THEKERNEL
->step_ticker
->synchronize_acceleration(true);
86 // Is this move finished ?
87 if( this->stepped
== this->steps_to_move
) {
88 // Mark it as finished, then StepTicker will call signal_mode_finished()
89 // This is so we don't call that before all the steps have been generated for this tick()
90 this->is_move_finished
= true;
91 THEKERNEL
->step_ticker
->a_move_finished
= true;
92 this->last_step_tick
= THEKERNEL
->step_ticker
->get_tick_cnt(); // remember when last step was
96 void StepperMotor::force_finish_move()
98 this->is_move_finished
= true;
99 THEKERNEL
->step_ticker
->a_move_finished
= true;
100 this->last_step_tick
= THEKERNEL
->step_ticker
->get_tick_cnt(); // remember when last step was
101 this->steps_to_move
= this->stepped
;
104 // If the move is finished, the StepTicker will call this ( because we asked it to in tick() )
105 void StepperMotor::signal_move_finished()
108 this->moving
= false;
109 this->steps_to_move
= 0;
110 this->minimum_step_rate
= default_minimum_actuator_rate
;
112 // signal it to whatever cares
113 // in this call a new block may start, new moves set and new speeds
114 this->end_hook
->call();
116 // We only need to do this if we were not instructed to move
117 if( !this->moving
) {
118 this->update_exit_tick();
121 this->is_move_finished
= false;
124 // This is just a way not to check for ( !this->moving || this->fx_ticks_per_step == 0 ) at every tick()
125 void StepperMotor::update_exit_tick()
127 if( !this->moving
|| this->steps_to_move
== 0 ) {
128 // No more ticks will be recieved and no more events from StepTicker
129 THEKERNEL
->step_ticker
->remove_motor_from_active_list(this);
131 // we will now get ticks and StepTIcker will send us events
132 THEKERNEL
->step_ticker
->add_motor_to_active_list(this);
136 // Instruct the StepperMotor to move a certain number of steps
137 StepperMotor
* StepperMotor::move( bool direction
, unsigned int steps
, float initial_speed
)
139 this->dir_pin
.set(direction
);
140 this->direction
= direction
;
142 // How many steps we have to move until the move is done
143 this->steps_to_move
= steps
;
145 // Zero our tool counters
147 this->fx_ticks_per_step
= 0xFFFFF000UL
; // some big number so we don't start stepping before it is set again
148 if(this->last_step_tick_valid
) {
149 // we set this based on when the last step was, thus compensating for missed ticks
150 uint32_t ts
= THEKERNEL
->step_ticker
->ticks_since(this->last_step_tick
);
151 // if an axis stops too soon then we can get a huge number of ticks here which causes problems, so if the number of ticks is too great we ignore them
152 // example of when this happens is when one axis is going very slow an the min 20steps/sec kicks in, the axis will reach its target much sooner leaving a long gap
153 // until the end of the block.
154 // TODO we may need to set this based on the current step rate, trouble is we don't know what that is yet, we could use the last fx_ticks_per_step as a guide
155 if(ts
> 5) ts
= 5; // limit to 50us catch up around 1-2 steps
156 else if(ts
> 15) ts
= 0; // no way to know what the delay was
157 this->fx_counter
= ts
*fx_increment
;
159 this->fx_counter
= 0; // set to zero as there was no step last block
162 // Starting now we are moving
164 if(initial_speed
>= 0.0F
) set_speed(initial_speed
);
167 this->moving
= false;
169 this->update_exit_tick();
173 // Set the speed at which this stepper moves in steps/sec, should be called set_step_rate()
174 // we need to make sure that we have a minimum speed here and that it fits the 32bit fixed point fx counters
175 // Note nothing will really ever go as slow as the minimum speed here, it is just forced to avoid bad errors
176 // fx_ticks_per_step is what actually sets the step rate, it is fixed point 18.14
177 StepperMotor
* StepperMotor::set_speed( float speed
)
179 if(speed
< minimum_step_rate
) {
180 speed
= minimum_step_rate
;
183 // if(speed <= 0.0F) { // we can't actually do 0 but we can get close, need to avoid divide by zero later on
184 // this->fx_ticks_per_step= 0xFFFFFFFFUL; // 0.381 steps/sec
185 // this->steps_per_second = THEKERNEL->step_ticker->get_frequency() / (this->fx_ticks_per_step >> fx_shift);
189 // How many steps we must output per second
190 this->steps_per_second
= speed
;
192 // set the new speed, NOTE this can be pre-empted by stepticker so the following write needs to be atomic
193 this->fx_ticks_per_step
= floor(fx_increment
* THEKERNEL
->step_ticker
->get_frequency() / speed
);
197 void StepperMotor::change_steps_per_mm(float new_steps
)
199 steps_per_mm
= new_steps
;
200 last_milestone_steps
= lroundf(last_milestone_mm
* steps_per_mm
);
201 current_position_steps
= last_milestone_steps
;
204 void StepperMotor::change_last_milestone(float new_milestone
)
206 last_milestone_mm
= new_milestone
;
207 last_milestone_steps
= lroundf(last_milestone_mm
* steps_per_mm
);
208 current_position_steps
= last_milestone_steps
;
211 int StepperMotor::steps_to_target(float target
)
213 int target_steps
= lroundf(target
* steps_per_mm
);
214 return target_steps
- last_milestone_steps
;