src/modules/tools/zprobe/ZProbe.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
   8 #include "ZProbe.h"
   9
  10 #include "Kernel.h"
  11 #include "BaseSolution.h"
  12 #include "Config.h"
  13 #include "Robot.h"
  14 #include "StepperMotor.h"
  15 #include "StreamOutputPool.h"
  16 #include "Gcode.h"
  17 #include "Conveyor.h"
  18 #include "Stepper.h"
  19 #include "checksumm.h"
  20 #include "ConfigValue.h"
  21 #include "SlowTicker.h"
  22 #include "Planner.h"
  23 #include "SerialMessage.h"
  24 #include "PublicDataRequest.h"
  25 #include "EndstopsPublicAccess.h"
  26 #include "PublicData.h"
  27 #include "LevelingStrategy.h"
  28 #include "StepTicker.h"
  29 #include "utils.h"
  30
  31 // strategies we know about
  32 #include "DeltaCalibrationStrategy.h"
  33 #include "ThreePointStrategy.h"
  34 #include "ZGridStrategy.h"
  35 #include "DeltaGridStrategy.h"
  36
  37 #define enable_checksum          CHECKSUM("enable")
  38 #define probe_pin_checksum       CHECKSUM("probe_pin")
  39 #define debounce_count_checksum  CHECKSUM("debounce_count")
  40 #define slow_feedrate_checksum   CHECKSUM("slow_feedrate")
  41 #define fast_feedrate_checksum   CHECKSUM("fast_feedrate")
  42 #define return_feedrate_checksum CHECKSUM("return_feedrate")
  43 #define probe_height_checksum    CHECKSUM("probe_height")
  44 #define gamma_max_checksum       CHECKSUM("gamma_max")
  45 #define reverse_z_direction_checksum CHECKSUM("reverse_z")
  46
  47 // from endstop section
  48 #define delta_homing_checksum    CHECKSUM("delta_homing")
  49 #define rdelta_homing_checksum    CHECKSUM("rdelta_homing")
  50
  51 #define X_AXIS 0
  52 #define Y_AXIS 1
  53 #define Z_AXIS 2
  54
  55 #define STEPPER THEKERNEL->robot->actuators
  56 #define STEPS_PER_MM(a) (STEPPER[a]->get_steps_per_mm())
  57 #define Z_STEPS_PER_MM STEPS_PER_MM(Z_AXIS)
  58
  59 #define abs(a) ((a<0) ? -a : a)
  60
  61 void ZProbe::on_module_loaded()
  62 {
  63     // if the module is disabled -> do nothing
  64     if(!THEKERNEL->config->value( zprobe_checksum, enable_checksum )->by_default(false)->as_bool()) {
  65         // as this module is not needed free up the resource
  66         delete this;
  67         return;
  68     }
  69
  70     // load settings
  71     this->on_config_reload(this);
  72     // register event-handlers
  73     register_for_event(ON_GCODE_RECEIVED);
  74
  75     THEKERNEL->step_ticker->register_acceleration_tick_handler([this](){acceleration_tick(); });
  76
  77     // we read the probe in this timer, currently only for G38 probes.
  78     probing= false;
  79     THEKERNEL->slow_ticker->attach(1000, this, &ZProbe::read_probe);
  80 }
  81
  82 void ZProbe::on_config_reload(void *argument)
  83 {
  84     this->pin.from_string( THEKERNEL->config->value(zprobe_checksum, probe_pin_checksum)->by_default("nc" )->as_string())->as_input();
  85     this->debounce_count = THEKERNEL->config->value(zprobe_checksum, debounce_count_checksum)->by_default(0  )->as_number();
  86
  87     // get strategies to load
  88     vector<uint16_t> modules;
  89     THEKERNEL->config->get_module_list( &modules, leveling_strategy_checksum);
  90     for( auto cs : modules ){
  91         if( THEKERNEL->config->value(leveling_strategy_checksum, cs, enable_checksum )->as_bool() ){
  92             bool found= false;
  93             // check with each known strategy and load it if it matches
  94             switch(cs) {
  95                 case delta_calibration_strategy_checksum:
  96                     this->strategies.push_back(new DeltaCalibrationStrategy(this));
  97                     found= true;
  98                     break;
  99
 100                 case three_point_leveling_strategy_checksum:
 101                     // NOTE this strategy is mutually exclusive with the delta calibration strategy
 102                     this->strategies.push_back(new ThreePointStrategy(this));
 103                     found= true;
 104                     break;
 105
 106                 case ZGrid_leveling_checksum:
 107                      this->strategies.push_back(new ZGridStrategy(this));
 108                      found= true;
 109                      break;
 110
 111                 case delta_grid_leveling_strategy_checksum:
 112                     this->strategies.push_back(new DeltaGridStrategy(this));
 113                     found= true;
 114                     break;
 115             }
 116             if(found) this->strategies.back()->handleConfig();
 117         }
 118     }
 119
 120     // need to know if we need to use delta kinematics for homing
 121     this->is_delta = THEKERNEL->config->value(delta_homing_checksum)->by_default(false)->as_bool();
 122     this->is_rdelta = THEKERNEL->config->value(rdelta_homing_checksum)->by_default(false)->as_bool();
 123
 124     // default for backwards compatibility add DeltaCalibrationStrategy if a delta
 125     // will be deprecated
 126     if(this->strategies.empty()) {
 127         if(this->is_delta) {
 128             this->strategies.push_back(new DeltaCalibrationStrategy(this));
 129             this->strategies.back()->handleConfig();
 130         }
 131     }
 132
 133     this->probe_height  = THEKERNEL->config->value(zprobe_checksum, probe_height_checksum)->by_default(5.0F)->as_number();
 134     this->slow_feedrate = THEKERNEL->config->value(zprobe_checksum, slow_feedrate_checksum)->by_default(5)->as_number(); // feedrate in mm/sec
 135     this->fast_feedrate = THEKERNEL->config->value(zprobe_checksum, fast_feedrate_checksum)->by_default(100)->as_number(); // feedrate in mm/sec
 136     this->return_feedrate = THEKERNEL->config->value(zprobe_checksum, return_feedrate_checksum)->by_default(0)->as_number(); // feedrate in mm/sec
 137     this->reverse_z     = THEKERNEL->config->value(zprobe_checksum, reverse_z_direction_checksum)->by_default(false)->as_bool(); // Z probe moves in reverse direction
 138     this->max_z         = THEKERNEL->config->value(gamma_max_checksum)->by_default(500)->as_number(); // maximum zprobe distance
 139 }
 140
 141 bool ZProbe::wait_for_probe(int& steps)
 142 {
 143     unsigned int debounce = 0;
 144     while(true) {
 145         THEKERNEL->call_event(ON_IDLE);
 146         if(THEKERNEL->is_halted()){
 147             // aborted by kill
 148             return false;
 149         }
 150
 151         bool delta= is_delta || is_rdelta;
 152
 153         // if no stepper is moving, moves are finished and there was no touch
 154         if( !STEPPER[Z_AXIS]->is_moving() && (!delta || (!STEPPER[Y_AXIS]->is_moving() && !STEPPER[Z_AXIS]->is_moving())) ) {
 155             return false;
 156         }
 157
 158         // if the probe is active...
 159         if( this->pin.get() ) {
 160             //...increase debounce counter...
 161             if( debounce < debounce_count) {
 162                 // ...but only if the counter hasn't reached the max. value
 163                 debounce++;
 164             } else {
 165                 // ...otherwise stop the steppers, return its remaining steps
 166                 if(STEPPER[Z_AXIS]->is_moving()){
 167                     steps= STEPPER[Z_AXIS]->get_stepped();
 168                     STEPPER[Z_AXIS]->move(0, 0);
 169                 }
 170                 if(delta) {
 171                     for( int i = X_AXIS; i <= Y_AXIS; i++ ) {
 172                         if ( STEPPER[i]->is_moving() ) {
 173                             STEPPER[i]->move(0, 0);
 174                         }
 175                     }
 176                 }
 177                 return true;
 178             }
 179         } else {
 180             // The probe was not hit yet, reset debounce counter
 181             debounce = 0;
 182         }
 183     }
 184 }
 185
 186 // single probe with custom feedrate
 187 // returns boolean value indicating if probe was triggered
 188 bool ZProbe::run_probe(int& steps, float feedrate, float max_dist, bool reverse)
 189 {
 190     // not a block move so disable the last tick setting
 191     for ( int c = X_AXIS; c <= Z_AXIS; c++ ) {
 192         STEPPER[c]->set_moved_last_block(false);
 193     }
 194
 195     // Enable the motors
 196     THEKERNEL->stepper->turn_enable_pins_on();
 197     this->current_feedrate = feedrate * Z_STEPS_PER_MM; // steps/sec
 198     float maxz= max_dist < 0 ? this->max_z*2 : max_dist;
 199
 200     // move Z down
 201     bool dir= (!reverse_z != reverse); // xor
 202     STEPPER[Z_AXIS]->move(dir, maxz * Z_STEPS_PER_MM, 0); // probe in specified direction, no more than maxz
 203     if(this->is_delta || this->is_rdelta) {
 204         // for delta need to move all three actuators
 205         STEPPER[X_AXIS]->move(dir, maxz * STEPS_PER_MM(X_AXIS), 0);
 206         STEPPER[Y_AXIS]->move(dir, maxz * STEPS_PER_MM(Y_AXIS), 0);
 207     }
 208
 209     // start acceleration processing
 210     this->running = true;
 211
 212     bool r = wait_for_probe(steps);
 213     this->running = false;
 214     STEPPER[X_AXIS]->move(0, 0);
 215     STEPPER[Y_AXIS]->move(0, 0);
 216     STEPPER[Z_AXIS]->move(0, 0);
 217     return r;
 218 }
 219
 220 bool ZProbe::return_probe(int steps, bool reverse)
 221 {
 222     // move probe back to where it was
 223
 224     float fr;
 225     if(this->return_feedrate != 0) { // use return_feedrate if set
 226         fr = this->return_feedrate;
 227     } else {
 228         fr = this->slow_feedrate*2; // nominally twice slow feedrate
 229         if(fr > this->fast_feedrate) fr = this->fast_feedrate; // unless that is greater than fast feedrate
 230     }
 231
 232     this->current_feedrate = fr * Z_STEPS_PER_MM; // feedrate in steps/sec
 233     bool dir= ((steps < 0) != reverse_z); // xor
 234
 235     if(reverse) dir= !dir;
 236     steps= abs(steps);
 237
 238     bool delta= (this->is_delta || this->is_rdelta);
 239     STEPPER[Z_AXIS]->move(dir, steps, 0);
 240     if(delta) {
 241         STEPPER[X_AXIS]->move(dir, steps, 0);
 242         STEPPER[Y_AXIS]->move(dir, steps, 0);
 243     }
 244
 245     this->running = true;
 246     while(STEPPER[Z_AXIS]->is_moving() || (delta && (STEPPER[X_AXIS]->is_moving() || STEPPER[Y_AXIS]->is_moving())) ) {
 247         // wait for it to complete
 248         THEKERNEL->call_event(ON_IDLE);
 249          if(THEKERNEL->is_halted()){
 250             // aborted by kill
 251             break;
 252         }
 253     }
 254
 255     this->running = false;
 256     STEPPER[X_AXIS]->move(0, 0);
 257     STEPPER[Y_AXIS]->move(0, 0);
 258     STEPPER[Z_AXIS]->move(0, 0);
 259
 260     return true;
 261 }
 262
 263 bool ZProbe::doProbeAt(int &steps, float x, float y)
 264 {
 265     int s;
 266     // move to xy
 267     coordinated_move(x, y, NAN, getFastFeedrate());
 268     if(!run_probe(s)) return false;
 269
 270     // return to original Z
 271     return_probe(s);
 272     steps = s;
 273
 274     return true;
 275 }
 276
 277 float ZProbe::probeDistance(float x, float y)
 278 {
 279     int s;
 280     if(!doProbeAt(s, x, y)) return NAN;
 281     return zsteps_to_mm(s);
 282 }
 283
 284 void ZProbe::on_gcode_received(void *argument)
 285 {
 286     Gcode *gcode = static_cast<Gcode *>(argument);
 287
 288     if( gcode->has_g && gcode->g >= 29 && gcode->g <= 32) {
 289
 290         // make sure the probe is defined and not already triggered before moving motors
 291         if(!this->pin.connected()) {
 292             gcode->stream->printf("ZProbe not connected.\n");
 293             return;
 294         }
 295         if(this->pin.get()) {
 296             gcode->stream->printf("ZProbe triggered before move, aborting command.\n");
 297             return;
 298         }
 299
 300         if( gcode->g == 30 ) { // simple Z probe
 301             // first wait for an empty queue i.e. no moves left
 302             THEKERNEL->conveyor->wait_for_empty_queue();
 303
 304             int steps;
 305             bool probe_result;
 306             bool reverse= (gcode->has_letter('R') && gcode->get_value('R') != 0); // specify to probe in reverse direction
 307             float rate= gcode->has_letter('F') ? gcode->get_value('F') / 60 : this->slow_feedrate;
 308             probe_result = run_probe(steps, rate, -1, reverse);
 309
 310             if(probe_result) {
 311                 // the result is in actuator coordinates and raw steps
 312                 gcode->stream->printf("Z:%1.4f C:%d\n", zsteps_to_mm(steps), steps);
 313
 314                 // set the last probe position to the current actuator units
 315                 THEKERNEL->robot->set_last_probe_position(std::make_tuple(
 316                     THEKERNEL->robot->actuators[X_AXIS]->get_current_position(),
 317                     THEKERNEL->robot->actuators[Y_AXIS]->get_current_position(),
 318                     THEKERNEL->robot->actuators[Z_AXIS]->get_current_position(),
 319                     1));
 320
 321                 // move back to where it started, unless a Z is specified (and not a rotary delta)
 322                 if(gcode->has_letter('Z') && !is_rdelta) {
 323                     // set Z to the specified value, and leave probe where it is
 324                     THEKERNEL->robot->reset_axis_position(gcode->get_value('Z'), Z_AXIS);
 325
 326                 } else {
 327                     // return to pre probe position
 328                     return_probe(steps, reverse);
 329                 }
 330
 331             } else {
 332                 gcode->stream->printf("ZProbe not triggered\n");
 333                 THEKERNEL->robot->set_last_probe_position(std::make_tuple(
 334                     THEKERNEL->robot->actuators[X_AXIS]->get_current_position(),
 335                     THEKERNEL->robot->actuators[Y_AXIS]->get_current_position(),
 336                     THEKERNEL->robot->actuators[Z_AXIS]->get_current_position(),
 337                     0));
 338             }
 339
 340         } else {
 341             if(!gcode->has_letter('P')) {
 342                 // find the first strategy to handle the gcode
 343                 for(auto s : strategies){
 344                     if(s->handleGcode(gcode)) {
 345                         return;
 346                     }
 347                 }
 348                 gcode->stream->printf("No strategy found to handle G%d\n", gcode->g);
 349
 350             }else{
 351                 // P paramater selects which strategy to send the code to
 352                 // they are loaded in the order they are defined in config, 0 being the first, 1 being the second and so on.
 353                 uint16_t i= gcode->get_value('P');
 354                 if(i < strategies.size()) {
 355                     if(!strategies[i]->handleGcode(gcode)){
 356                         gcode->stream->printf("strategy #%d did not handle G%d\n", i, gcode->g);
 357                     }
 358                     return;
 359
 360                 }else{
 361                     gcode->stream->printf("strategy #%d is not loaded\n", i);
 362                 }
 363             }
 364         }
 365
 366     } else if(gcode->has_g && gcode->g == 38 ) { // G38.2 Straight Probe with error, G38.3 straight probe without error
 367         // linuxcnc/grbl style probe http://www.linuxcnc.org/docs/2.5/html/gcode/gcode.html#sec:G38-probe
 368         if(gcode->subcode != 2 && gcode->subcode != 3) {
 369             gcode->stream->printf("error:Only G38.2 and G38.3 are supported\n");
 370             return;
 371         }
 372
 373         // make sure the probe is defined and not already triggered before moving motors
 374         if(!this->pin.connected()) {
 375             gcode->stream->printf("error:ZProbe not connected.\n");
 376             return;
 377         }
 378
 379         if(this->pin.get()) {
 380             gcode->stream->printf("error:ZProbe triggered before move, aborting command.\n");
 381             return;
 382         }
 383
 384         // first wait for an empty queue i.e. no moves left
 385         THEKERNEL->conveyor->wait_for_empty_queue();
 386
 387         // turn off any compensation transform
 388         auto savect= THEKERNEL->robot->compensationTransform;
 389         THEKERNEL->robot->compensationTransform= nullptr;
 390
 391         if(gcode->has_letter('X')) {
 392             // probe in the X axis
 393             probe_XYZ(gcode, X_AXIS);
 394
 395         }else if(gcode->has_letter('Y')) {
 396             // probe in the Y axis
 397             probe_XYZ(gcode, Y_AXIS);
 398
 399         }else if(gcode->has_letter('Z')) {
 400             // probe in the Z axis
 401             probe_XYZ(gcode, Z_AXIS);
 402
 403         }else{
 404             gcode->stream->printf("error:at least one of X Y or Z must be specified\n");
 405         }
 406
 407         // restore compensationTransform
 408         THEKERNEL->robot->compensationTransform= savect;
 409
 410         return;
 411
 412     } else if(gcode->has_m) {
 413         // M code processing here
 414         int c;
 415         switch (gcode->m) {
 416             case 119:
 417                 c = this->pin.get();
 418                 gcode->stream->printf(" Probe: %d", c);
 419                 gcode->add_nl = true;
 420                 break;
 421
 422             case 670:
 423                 if (gcode->has_letter('S')) this->slow_feedrate = gcode->get_value('S');
 424                 if (gcode->has_letter('K')) this->fast_feedrate = gcode->get_value('K');
 425                 if (gcode->has_letter('R')) this->return_feedrate = gcode->get_value('R');
 426                 if (gcode->has_letter('Z')) this->max_z = gcode->get_value('Z');
 427                 if (gcode->has_letter('H')) this->probe_height = gcode->get_value('H');
 428                 if (gcode->has_letter('I')) { // NOTE this is temporary and toggles the invertion status of the pin
 429                     invert_override= (gcode->get_value('I') != 0);
 430                     pin.set_inverting(pin.is_inverting() != invert_override); // XOR so inverted pin is not inverted and vice versa
 431                 }
 432                 break;
 433
 434             case 500: // save settings
 435             case 503: // print settings
 436                 gcode->stream->printf(";Probe feedrates Slow/fast(K)/Return (mm/sec) max_z (mm) height (mm):\nM670 S%1.2f K%1.2f R%1.2f Z%1.2f H%1.2f\n",
 437                     this->slow_feedrate, this->fast_feedrate, this->return_feedrate, this->max_z, this->probe_height);
 438
 439                 // fall through is intended so leveling strategies can handle m-codes too
 440
 441             default:
 442                 for(auto s : strategies){
 443                     if(s->handleGcode(gcode)) {
 444                         return;
 445                     }
 446                 }
 447         }
 448     }
 449 }
 450
 451 uint32_t ZProbe::read_probe(uint32_t dummy)
 452 {
 453     if(!probing || probe_detected) return 0;
 454
 455     // TODO add debounce/noise filter
 456     if(this->pin.get()) {
 457         probe_detected= true;
 458         // now tell all the stepper_motors to stop
 459         for(auto &a : THEKERNEL->robot->actuators) a->force_finish_move();
 460     }
 461     return 0;
 462 }
 463
 464 // special way to probe in the X or Y or Z direction using planned moves, should work with any kinematics
 465 void ZProbe::probe_XYZ(Gcode *gcode, int axis)
 466 {
 467     // enable the probe checking in the timer
 468     probing= true;
 469     probe_detected= false;
 470     THEKERNEL->robot->disable_segmentation= true; // we must disable segmentation as this won't work with it enabled (beware on deltas probing in X or Y)
 471
 472     // get probe feedrate if specified
 473     float rate = (gcode->has_letter('F')) ? gcode->get_value('F')*60 : this->slow_feedrate;
 474
 475     // do a regular move which will stop as soon as the probe is triggered, or the distance is reached
 476     switch(axis) {
 477         case X_AXIS: coordinated_move(gcode->get_value('X'), 0, 0, rate, true); break;
 478         case Y_AXIS: coordinated_move(0, gcode->get_value('Y'), 0, rate, true); break;
 479         case Z_AXIS: coordinated_move(0, 0, gcode->get_value('Z'), rate, true); break;
 480     }
 481
 482     // coordinated_move returns when the move is finished
 483
 484     // disable probe checking
 485     probing= false;
 486     THEKERNEL->robot->disable_segmentation= false;
 487
 488     float pos[3];
 489     {
 490         // get the current position
 491         ActuatorCoordinates current_position{
 492             THEKERNEL->robot->actuators[X_AXIS]->get_current_position(),
 493             THEKERNEL->robot->actuators[Y_AXIS]->get_current_position(),
 494             THEKERNEL->robot->actuators[Z_AXIS]->get_current_position()
 495         };
 496
 497         // get machine position from the actuator position using FK
 498         THEKERNEL->robot->arm_solution->actuator_to_cartesian(current_position, pos);
 499     }
 500
 501     uint8_t probeok= this->probe_detected ? 1 : 0;
 502
 503     // print results using the GRBL format
 504     gcode->stream->printf("[PRB:%1.3f,%1.3f,%1.3f:%d]\n", pos[X_AXIS], pos[Y_AXIS], pos[Z_AXIS], probeok);
 505     THEKERNEL->robot->set_last_probe_position(std::make_tuple(pos[X_AXIS], pos[Y_AXIS], pos[Z_AXIS], probeok));
 506
 507     if(!probeok && gcode->subcode == 2) {
 508         // issue error if probe was not triggered and subcode == 2
 509         gcode->stream->printf("ALARM:Probe fail\n");
 510         THEKERNEL->call_event(ON_HALT, nullptr);
 511
 512     }else if(probeok){
 513         // if the probe stopped the move we need to correct the last_milestone as it did not reach where it thought
 514         THEKERNEL->robot->reset_position_from_current_actuator_position();
 515     }
 516 }
 517
 518 // Called periodically to change the speed to match acceleration
 519 void ZProbe::acceleration_tick(void)
 520 {
 521     if(!this->running) return; // nothing to do
 522     if(STEPPER[Z_AXIS]->is_moving()) accelerate(Z_AXIS);
 523
 524     if(is_delta || is_rdelta) {
 525          // deltas needs to move all actuators
 526         for ( int c = X_AXIS; c <= Y_AXIS; c++ ) {
 527             if( !STEPPER[c]->is_moving() ) continue;
 528             accelerate(c);
 529         }
 530     }
 531
 532     return;
 533 }
 534
 535 void ZProbe::accelerate(int c)
 536 {   uint32_t current_rate = STEPPER[c]->get_steps_per_second();
 537     uint32_t target_rate = floorf(this->current_feedrate);
 538
 539     // Z may have a different acceleration to X and Y
 540     float acc= (c==Z_AXIS) ? THEKERNEL->planner->get_z_acceleration() : THEKERNEL->planner->get_acceleration();
 541     if( current_rate < target_rate ) {
 542         uint32_t rate_increase = floorf((acc / THEKERNEL->acceleration_ticks_per_second) * STEPS_PER_MM(c));
 543         current_rate = min( target_rate, current_rate + rate_increase );
 544     }
 545     if( current_rate > target_rate ) {
 546         current_rate = target_rate;
 547     }
 548
 549     // steps per second
 550     STEPPER[c]->set_speed(current_rate);
 551 }
 552
 553 // issue a coordinated move directly to robot, and return when done
 554 // Only move the coordinates that are passed in as not nan
 555 // NOTE must use G53 to force move in machine coordiantes and ignore any WCS offsetts
 556 void ZProbe::coordinated_move(float x, float y, float z, float feedrate, bool relative)
 557 {
 558     char buf[32];
 559     char cmd[64];
 560
 561     if(relative) strcpy(cmd, "G91 G0 ");
 562     else strcpy(cmd, "G53 G0 "); // G53 forces movement in machine coordinate system
 563
 564     if(!isnan(x)) {
 565         int n = snprintf(buf, sizeof(buf), " X%1.3f", x);
 566         strncat(cmd, buf, n);
 567     }
 568     if(!isnan(y)) {
 569         int n = snprintf(buf, sizeof(buf), " Y%1.3f", y);
 570         strncat(cmd, buf, n);
 571     }
 572     if(!isnan(z)) {
 573         int n = snprintf(buf, sizeof(buf), " Z%1.3f", z);
 574         strncat(cmd, buf, n);
 575     }
 576
 577     // use specified feedrate (mm/sec)
 578     int n = snprintf(buf, sizeof(buf), " F%1.1f", feedrate * 60); // feed rate is converted to mm/min
 579     strncat(cmd, buf, n);
 580     if(relative) strcat(cmd, " G90");
 581
 582     //THEKERNEL->streams->printf("DEBUG: move: %s\n", cmd);
 583
 584     // send as a command line as may have multiple G codes in it
 585     struct SerialMessage message;
 586     message.message = cmd;
 587     message.stream = &(StreamOutput::NullStream);
 588     THEKERNEL->call_event(ON_CONSOLE_LINE_RECEIVED, &message );
 589     THEKERNEL->conveyor->wait_for_empty_queue();
 590 }
 591
 592 // issue home command
 593 void ZProbe::home()
 594 {
 595     Gcode gc("G28", &(StreamOutput::NullStream));
 596     THEKERNEL->call_event(ON_GCODE_RECEIVED, &gc);
 597 }
 598
 599 float ZProbe::zsteps_to_mm(float steps)
 600 {
 601     return steps / Z_STEPS_PER_MM;
 602 }