NOTES.txt

SPECIAL COMMANDS
  
#define CMD_STATUS_REPORT '?'
#define CMD_FEED_HOLD '!'
#define CMD_CYCLE_START '~'
#define CMD_RESET 0x18 // ctrl-x

SUPPORTED GrbL GCODES

// Pass 1: Commands
  while(next_statement(&letter, &value, line, &char_counter)) {
    int_value = trunc(value);
    switch(letter) {
      case 'G':
        switch(int_value) {
          case 0: gc.motion_mode = MOTION_MODE_SEEK; break;
          case 1: gc.motion_mode = MOTION_MODE_LINEAR; break;
          case 2: gc.motion_mode = MOTION_MODE_CW_ARC; break;
          case 3: gc.motion_mode = MOTION_MODE_CCW_ARC; break;
          case 4: next_action = NEXT_ACTION_DWELL; break;
          case 17: select_plane(X_AXIS, Y_AXIS, Z_AXIS); break;
          case 18: select_plane(X_AXIS, Z_AXIS, Y_AXIS); break;
          case 19: select_plane(Y_AXIS, Z_AXIS, X_AXIS); break;
          case 20: gc.inches_mode = true; break;
          case 21: gc.inches_mode = false; break;
          case 28: case 30: next_action = NEXT_ACTION_GO_HOME; break;
          case 53: absolute_override = true; break;
          case 80: gc.motion_mode = MOTION_MODE_CANCEL; break;        
          case 90: gc.absolute_mode = true; break;
          case 91: gc.absolute_mode = false; break;
          case 92: next_action = NEXT_ACTION_SET_COORDINATE_OFFSET; break;        
          case 93: gc.inverse_feed_rate_mode = true; break;
          case 94: gc.inverse_feed_rate_mode = false; break;
          default: FAIL(STATUS_UNSUPPORTED_STATEMENT);
        }
        break;
      case 'M':
        switch(int_value) {
          case 0: case 60: gc.program_flow = PROGRAM_FLOW_PAUSED; break; // Program pause
          case 1: gc.program_flow = PROGRAM_FLOW_OPT_PAUSED; break; // Program pause with optional stop on
          case 2: case 30: gc.program_flow = PROGRAM_FLOW_COMPLETED; break; // Program end and reset 
          case 3: gc.spindle_direction = 1; break;
          case 4: gc.spindle_direction = -1; break;
          case 5: gc.spindle_direction = 0; break;
          default: FAIL(STATUS_UNSUPPORTED_STATEMENT);
        }            
        break;
      case 'T': gc.tool = trunc(value); break;
    }
    if(gc.status_code) { break; }
  }
  
  // If there were any errors parsing this line, we will return right away with the bad news
  if (gc.status_code) { return(gc.status_code); }

  char_counter = 0;
  clear_vector(target);
  clear_vector(offset);
  memcpy(target, gc.position, sizeof(target)); // i.e. target = gc.position

  // Pass 2: Parameters
  while(next_statement(&letter, &value, line, &char_counter)) {
    int_value = trunc(value);
    unit_converted_value = to_millimeters(value);
    switch(letter) {
      case 'F': 
        if (unit_converted_value <= 0) { FAIL(STATUS_BAD_NUMBER_FORMAT); } // Must be greater than zero
        if (gc.inverse_feed_rate_mode) {
          inverse_feed_rate = unit_converted_value; // seconds per motion for this motion only
        } else {          
          if (gc.motion_mode == MOTION_MODE_SEEK) {
            gc.seek_rate = unit_converted_value;
          } else {
            gc.feed_rate = unit_converted_value; // millimeters per minute
          }
        }
        break;
      case 'I': case 'J': case 'K': offset[letter-'I'] = unit_converted_value; break;
      case 'P': p = value; break;
      case 'R': r = unit_converted_value; radius_mode = true; break;
      case 'S': gc.spindle_speed = value; break;
      case 'X': case 'Y': case 'Z':
        if (gc.absolute_mode || absolute_override) {
          target[letter - 'X'] = unit_converted_value;
        } else {
          target[letter - 'X'] += unit_converted_value;
        }
        break;
    }
  }


/* 
  Intentionally not supported:

  - Canned cycles
  - Tool radius compensation
  - A,B,C-axes
  - Multiple coordinate systems
  - Evaluation of expressions
  - Variables
  - Multiple home locations
  - Probing
  - Override control

   group 0 = {G10, G28, G30, G92.1, G92.2, G92.3} (Non modal G-codes)
   group 8 = {M7, M8, M9} coolant (special case: M7 and M8 may be active at the same time)
   group 9 = {M48, M49} enable/disable feed and speed override switches
   group 12 = {G54, G55, G56, G57, G58, G59, G59.1, G59.2, G59.3} coordinate system selection
   group 13 = {G61, G61.1, G64} path control mode
*/

COMPILE TIME OPTIONS

#if REPORT_INCH_MODE
  #define DECIMAL_PLACES 3
  #define DECIMAL_MULTIPLIER 1000 // 10^DECIMAL_PLACES
#else
  #define DECIMAL_PLACES 2  // mm-mode
  #define DECIMAL_MULTIPLIER 100
#endif

Reporting units is compile time option

 #if REPORT_INCH_MODE
   printString("MPos:["); printFloat(print_position[X_AXIS]/(settings.steps_per_mm[X_AXIS]*MM_PER_INCH));
   printString(","); printFloat(print_position[Y_AXIS]/(settings.steps_per_mm[Y_AXIS]*MM_PER_INCH));
   printString(","); printFloat(print_position[Z_AXIS]/(settings.steps_per_mm[Z_AXIS]*MM_PER_INCH));
   printString("],WPos:["); printFloat((print_position[X_AXIS]-sys.coord_offset[X_AXIS])/(settings.steps_per_mm[X_AXIS]*MM_PER_INCH));
   printString(","); printFloat((print_position[Y_AXIS]-sys.coord_offset[Y_AXIS])/(settings.steps_per_mm[Y_AXIS]*MM_PER_INCH));
   printString(","); printFloat((print_position[Z_AXIS]-sys.coord_offset[Z_AXIS])/(settings.steps_per_mm[Z_AXIS]*MM_PER_INCH));
 #else
   printString("MPos:["); printFloat(print_position[X_AXIS]/(settings.steps_per_mm[X_AXIS]));
   printString(","); printFloat(print_position[Y_AXIS]/(settings.steps_per_mm[Y_AXIS]));
   printString(","); printFloat(print_position[Z_AXIS]/(settings.steps_per_mm[Z_AXIS]));
   printString("],WPos:["); printFloat((print_position[X_AXIS]-sys.coord_offset[X_AXIS])/(settings.steps_per_mm[X_AXIS]));
   printString(","); printFloat((print_position[Y_AXIS]-sys.coord_offset[Y_AXIS])/(settings.steps_per_mm[Y_AXIS]));
   printString(","); printFloat((print_position[Z_AXIS]-sys.coord_offset[Z_AXIS])/(settings.steps_per_mm[Z_AXIS]));
 #endif