gcode_process.c

#include	"gcode_process.h"

/** \file
	\brief Work out what to do with received G-Code commands
*/

#include	<string.h>

#include	"gcode_parse.h"

#include "cpu.h"
#include	"dda.h"
#include	"dda_queue.h"
#include	"watchdog.h"
#include	"delay.h"
#include	"serial.h"
#include	"temp.h"
#include	"heater.h"
#include	"timer.h"
#include	"sersendf.h"
#include	"pinio.h"
#include	"debug.h"
#include	"clock.h"
#include	"config_wrapper.h"
#include	"home.h"
#include "sd.h"
#include "bed_leveling.h"

/// the current tool
uint8_t tool;

/// the tool to be changed when we get an M6
uint8_t next_tool;

/************************************************************************//**

  \brief Processes command stored in global \ref next_target.
  This is where we work out what to actually do with each command we
    receive. All data has already been scaled to integers in gcode_process.
    If you want to add support for a new G or M code, this is the place.


*//*************************************************************************/

void process_gcode_command() {
	uint32_t	backup_f;

	// convert relative to absolute
	if (next_target.option_all_relative) {
    next_target.target.axis[X] += startpoint.axis[X];
    next_target.target.axis[Y] += startpoint.axis[Y];
    next_target.target.axis[Z] += startpoint.axis[Z];
	}

	// E relative movement.
	// Matches Sprinter's behaviour as of March 2012.
	if (next_target.option_e_relative)
		next_target.target.e_relative = 1;
	else
		next_target.target.e_relative = 0;

	if (next_target.option_all_relative && !next_target.option_e_relative)
		next_target.target.axis[E] += startpoint.axis[E];

	// implement axis limits
	#ifdef	X_MIN
    if (next_target.target.axis[X] < (int32_t)(X_MIN * 1000.))
      next_target.target.axis[X] = (int32_t)(X_MIN * 1000.);
	#endif
	#ifdef	X_MAX
    if (next_target.target.axis[X] > (int32_t)(X_MAX * 1000.))
      next_target.target.axis[X] = (int32_t)(X_MAX * 1000.);
	#endif
	#ifdef	Y_MIN
    if (next_target.target.axis[Y] < (int32_t)(Y_MIN * 1000.))
      next_target.target.axis[Y] = (int32_t)(Y_MIN * 1000.);
	#endif
	#ifdef	Y_MAX
    if (next_target.target.axis[Y] > (int32_t)(Y_MAX * 1000.))
      next_target.target.axis[Y] = (int32_t)(Y_MAX * 1000.);
	#endif
	#ifdef	Z_MIN
    if (next_target.target.axis[Z] < (int32_t)(Z_MIN * 1000.))
      next_target.target.axis[Z] = (int32_t)(Z_MIN * 1000.);
	#endif
	#ifdef	Z_MAX
    if (next_target.target.axis[Z] > (int32_t)(Z_MAX * 1000.))
      next_target.target.axis[Z] = (int32_t)(Z_MAX * 1000.);
	#endif

	// The GCode documentation was taken from http://reprap.org/wiki/Gcode .

	if (next_target.seen_T) {
	    //? --- T: Select Tool ---
	    //?
	    //? Example: T1
	    //?
	    //? Select extruder number 1 to build with.  Extruder numbering starts at 0.

	    next_tool = next_target.T;
	}

	if (next_target.seen_G) {
		uint8_t axisSelected = 0;

		switch (next_target.G) {
			case 0:
				//? G0: Rapid Linear Motion
				//?
				//? Example: G0 X12
				//?
				//? In this case move rapidly to X = 12 mm.  In fact, the RepRap firmware uses exactly the same code for rapid as it uses for controlled moves (see G1 below), as - for the RepRap machine - this is just as efficient as not doing so.  (The distinction comes from some old machine tools that used to move faster if the axes were not driven in a straight line.  For them G0 allowed any movement in space to get to the destination as fast as possible.)
				//?
        temp_wait();
				backup_f = next_target.target.F;
				next_target.target.F = MAXIMUM_FEEDRATE_X * 2L;
				enqueue(&next_target.target);
				next_target.target.F = backup_f;
				break;

			case 1:
				//? --- G1: Linear Motion at Feed Rate ---
				//?
				//? Example: G1 X90.6 Y13.8 E22.4
				//?
				//? Go in a straight line from the current (X, Y) point to the point (90.6, 13.8), extruding material as the move happens from the current extruded length to a length of 22.4 mm.
				//?
        temp_wait();
				enqueue(&next_target.target);
				break;

				//	G2 - Arc Clockwise
				// unimplemented

				//	G3 - Arc Counter-clockwise
				// unimplemented

			case 4:
				//? --- G4: Dwell ---
				//?
				//? Example: G4 P200
				//?
				//? In this case sit still doing nothing for 200 milliseconds.  During delays the state of the machine (for example the temperatures of its extruders) will still be preserved and controlled.
				//?
				queue_wait();
				// delay
				if (next_target.seen_P) {
					for (;next_target.P > 0;next_target.P--) {
						clock();
						delay_ms(1);
					}
				}
				break;

			case 20:
				//? --- G20: Set Units to Inches ---
				//?
				//? Example: G20
				//?
				//? Units from now on are in inches.
				//?
				next_target.option_inches = 1;
				break;

			case 21:
				//? --- G21: Set Units to Millimeters ---
				//?
				//? Example: G21
				//?
				//? Units from now on are in millimeters.  (This is the RepRap default.)
				//?
				next_target.option_inches = 0;
				break;

			case 28:
				//? --- G28: Home ---
				//?
				//? Example: G28
				//?
        //? This causes the RepRap machine to search for its X, Y and Z
        //? endstops. It does so at high speed, so as to get there fast. When
        //? it arrives it backs off slowly until the endstop is released again.
        //? Backing off slowly ensures more accurate positioning.
				//?
        //? If you add axis characters, then just the axes specified will be
        //? seached. Thus
				//?
        //?   G28 X Y72.3
				//?
        //? will zero the X and Y axes, but not Z. Coordinate values are
        //? ignored.
				//?

				queue_wait();

				if (next_target.seen_X) {
					#if defined	X_MIN_PIN
						home_x_negative();
					#elif defined X_MAX_PIN
						home_x_positive();
					#endif
					axisSelected = 1;
				}
				if (next_target.seen_Y) {
					#if defined	Y_MIN_PIN
						home_y_negative();
					#elif defined Y_MAX_PIN
						home_y_positive();
					#endif
					axisSelected = 1;
				}
				if (next_target.seen_Z) {
          #if defined Z_MIN_PIN
            home_z_negative();
          #elif defined Z_MAX_PIN
            home_z_positive();
					#endif
					axisSelected = 1;
				}
				// there's no point in moving E, as E has no endstops

				if (!axisSelected) {
					home();
				}
				break;

#ifdef BED_LEVELING
      case 29:
        //? --- G29: Bed leveling registration ---
        //?
        //? Example: G29 S1
        //?
        //? Registers the Z-offset for a specific point on the print bed.
        //? In this case the current position is used as the registration
        //? point, but a different position can be specified by including
        //? the X, Y and Z coordinate values.
        //?
        //? Three points must be registered before the dynamic bed leveling
        //? feature is activated. Once three points are registered, the bed
        //? is mapped assuming a flat plane and Z-offsets are adjusted
        //? automatically during movements to follow the mapped plane. The
        //? adjusted position is not displayed to the client, for example
        //? in M114 results.
        //?
        //? The S value controls the action as follows:
        //?   S0 displays the current bed leveling status
        //?   S1 registers a new point on the 3-point plane mapping
        //?   S5 clears all registered points and disables dynamic leveling
        //?
        //?   G29 S1 X100 Y50 Z-0.3
        //?
        //? This command registers the specific point 100,50 => -0.3
        //?
        //?   G29 S1
        //?
        //? This command registers the current head position as a point in
        //? the plane map.
        //?

        queue_wait();

        if (next_target.seen_S) {
          switch (next_target.S) {
            case 5:   // reset bed leveling registration points
              bed_level_reset();
              break;

            case 1:   // Register a new registration point
              bed_level_register(next_target.target.axis[X], next_target.target.axis[Y], next_target.target.axis[Z]);
              break;

            case 0:   // Report leveling status
              bed_level_report();
              break;
          }
        }

        // Restore position, ignoring any axes included in G29 cmd
        next_target.target = startpoint;
        break;
#endif /* BED_LEVELING */

			case 90:
				//? --- G90: Set to Absolute Positioning ---
				//?
				//? Example: G90
				//?
				//? All coordinates from now on are absolute relative to the origin
				//? of the machine. This is the RepRap default.
				//?
				//? If you ever want to switch back and forth between relative and
				//? absolute movement keep in mind, X, Y and Z follow the machine's
				//? coordinate system while E doesn't change it's position in the
				//? coordinate system on relative movements.
				//?

				// No wait_queue() needed.
				next_target.option_all_relative = 0;
				break;

			case 91:
				//? --- G91: Set to Relative Positioning ---
				//?
				//? Example: G91
				//?
				//? All coordinates from now on are relative to the last position.
				//?

				// No wait_queue() needed.
				next_target.option_all_relative = 1;
				break;

			case 92:
				//? --- G92: Set Position ---
				//?
				//? Example: G92 X10 E90
				//?
				//? Allows programming of absolute zero point, by reseting the current position to the values specified.  This would set the machine's X coordinate to 10, and the extrude coordinate to 90. No physical motion will occur.
				//?

				queue_wait();

				if (next_target.seen_X) {
          startpoint.axis[X] = next_target.target.axis[X];
					axisSelected = 1;
				}
				if (next_target.seen_Y) {
          startpoint.axis[Y] = next_target.target.axis[Y];
					axisSelected = 1;
				}
				if (next_target.seen_Z) {
          startpoint.axis[Z] = next_target.target.axis[Z];
					axisSelected = 1;
				}
				if (next_target.seen_E) {
          startpoint.axis[E] = next_target.target.axis[E];
					axisSelected = 1;
				}

				if (axisSelected == 0) {
          startpoint.axis[X] = next_target.target.axis[X] =
          startpoint.axis[Y] = next_target.target.axis[Y] =
          startpoint.axis[Z] = next_target.target.axis[Z] =
          startpoint.axis[E] = next_target.target.axis[E] = 0;
				}

				dda_new_startpoint();
				break;

			case 161:
				//? --- G161: Home negative ---
				//?
				//? Find the minimum limit of the specified axes by searching for the limit switch.
				//?
        #if defined X_MIN_PIN
          if (next_target.seen_X)
            home_x_negative();
        #endif
        #if defined Y_MIN_PIN
          if (next_target.seen_Y)
            home_y_negative();
        #endif
        #if defined Z_MIN_PIN
          if (next_target.seen_Z)
            home_z_negative();
        #endif
				break;

			case 162:
				//? --- G162: Home positive ---
				//?
				//? Find the maximum limit of the specified axes by searching for the limit switch.
				//?
        #if defined X_MAX_PIN
          if (next_target.seen_X)
            home_x_positive();
        #endif
        #if defined Y_MAX_PIN
          if (next_target.seen_Y)
            home_y_positive();
        #endif
        #if defined Z_MAX_PIN
          if (next_target.seen_Z)
            home_z_positive();
        #endif
				break;

				// unknown gcode: spit an error
			default:
				sersendf_P(PSTR("E: Bad G-code %d\n"), next_target.G);
				return;
		}
	}
	else if (next_target.seen_M) {
		uint8_t i;

		switch (next_target.M) {
			case 0:
				//? --- M0: machine stop ---
				//?
				//? Example: M0
				//?
				//? http://linuxcnc.org/handbook/RS274NGC_3/RS274NGC_33a.html#1002379
				//? Unimplemented, especially the restart after the stop. Fall trough to M2.
				//?

			case 2:
      case 84: // For compatibility with slic3rs default end G-code.
				//? --- M2: program end ---
				//?
				//? Example: M2
				//?
				//? http://linuxcnc.org/handbook/RS274NGC_3/RS274NGC_33a.html#1002379
				//?
				queue_wait();
				for (i = 0; i < NUM_HEATERS; i++)
					temp_set(i, 0);
				power_off();
        serial_writestr_P(PSTR("\nstop\n"));
				break;

			case 6:
				//? --- M6: tool change ---
				//?
				//? Undocumented.
				tool = next_tool;
				break;

      #ifdef SD
      case 20:
        //? --- M20: list SD card. ---
        sd_list("/");
        break;

      case 21:
        //? --- M21: initialise SD card. ---
        //?
        //? Has to be done before doing any other operation, including M20.
        sd_mount();
        break;

      case 22:
        //? --- M22: release SD card. ---
        //?
        //? Not mandatory. Just removing the card is fine, but results in
        //? odd behaviour when trying to read from the card anyways. M22
        //? makes also sure SD card printing is disabled, even with the card
        //? inserted.
        sd_unmount();
        break;

      case 23:
        //? --- M23: select file. ---
        //?
        //? This opens a file for reading. This file is valid up to M22 or up
        //? to the next M23.
        sd_open(gcode_str_buf);
        break;

      case 24:
        //? --- M24: start/resume SD print. ---
        //?
        //? This makes the SD card available as a G-code source. File is the
        //? one selected with M23.
        gcode_sources |= GCODE_SOURCE_SD;
        break;

      case 25:
        //? --- M25: pause SD print. ---
        //?
        //? This removes the SD card from the bitfield of available G-code
        //? sources. The file is kept open. The position inside the file
        //? is kept as well, to allow resuming.
        gcode_sources &= ! GCODE_SOURCE_SD;
        break;
      #endif /* SD */

			case 82:
				//? --- M82 - Set E codes absolute ---
				//?
				//? This is the default and overrides G90/G91.
				//? M82/M83 is not documented in the RepRap wiki, behaviour
				//? was taken from Sprinter as of March 2012.
				//?
				//? While E does relative movements, it doesn't change its
				//? position in the coordinate system. See also comment on G90.
				//?

				// No wait_queue() needed.
				next_target.option_e_relative = 0;
				break;

			case 83:
				//? --- M83 - Set E codes relative ---
				//?
				//? Counterpart to M82.
				//?

				// No wait_queue() needed.
				next_target.option_e_relative = 1;
				break;

			// M3/M101- extruder on
			case 3:
			case 101:
				//? --- M101: extruder on ---
				//?
				//? Undocumented.
        temp_wait();
				#ifdef DC_EXTRUDER
					heater_set(DC_EXTRUDER, DC_EXTRUDER_PWM);
				#endif
				break;

			// M5/M103- extruder off
			case 5:
			case 103:
				//? --- M103: extruder off ---
				//?
				//? Undocumented.
				#ifdef DC_EXTRUDER
					heater_set(DC_EXTRUDER, 0);
				#endif
				break;

			case 104:
				//? --- M104: Set Extruder Temperature (Fast) ---
				//?
				//? Example: M104 S190
				//?
        //? Set the temperature of the current extruder to 190<sup>o</sup>C
        //? and return control to the host immediately (''i.e.'' before that
        //? temperature has been reached by the extruder). For waiting, see M116.
        //?
        //? Teacup supports an optional P parameter as a zero-based temperature
        //? sensor index to address (e.g. M104 P1 S100 will set the temperature
        //? of the heater connected to the second temperature sensor rather
        //? than the extruder temperature).
        //?
				if ( ! next_target.seen_S)
					break;
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				temp_set(next_target.P, next_target.S);
				break;

			case 105:
        //? --- M105: Get Temperature(s) ---
				//?
				//? Example: M105
				//?
        //? Request the temperature of the current extruder and the build base
        //? in degrees Celsius. For example, the line sent to the host in
        //? response to this command looks like
				//?
				//? <tt>ok T:201 B:117</tt>
				//?
        //? Teacup supports an optional P parameter as a zero-based temperature
        //? sensor index to address.
				//?
				#ifdef ENFORCE_ORDER
					queue_wait();
				#endif
				if ( ! next_target.seen_P)
					next_target.P = TEMP_SENSOR_none;
				temp_print(next_target.P);
				break;

			case 7:
			case 106:
				//? --- M106: Set Fan Speed / Set Device Power ---
				//?
				//? Example: M106 S120
				//?
				//? Control the cooling fan (if any).
				//?
        //? Teacup supports an optional P parameter as a zero-based heater
        //? index to address. The heater index can differ from the temperature
        //? sensor index, see config.h.

				#ifdef ENFORCE_ORDER
					// wait for all moves to complete
					queue_wait();
				#endif
        if ( ! next_target.seen_P)
          #ifdef HEATER_FAN
            next_target.P = HEATER_FAN;
          #else
            next_target.P = 0;
          #endif
				if ( ! next_target.seen_S)
					break;
        heater_set(next_target.P, next_target.S);
				break;

			case 110:
				//? --- M110: Set Current Line Number ---
				//?
				//? Example: N123 M110
				//?
				//? Set the current line number to 123.  Thus the expected next line after this command will be 124.
				//? This is a no-op in Teacup.
				//?
				break;

      #ifdef DEBUG
			case 111:
				//? --- M111: Set Debug Level ---
				//?
				//? Example: M111 S6
				//?
				//? Set the level of debugging information transmitted back to the host to level 6.  The level is the OR of three bits:
				//?
				//? <Pre>
				//? #define         DEBUG_PID       1
				//? #define         DEBUG_DDA       2
				//? #define         DEBUG_POSITION  4
				//? </pre>
				//?
				//? This command is only available in DEBUG builds of Teacup.

				if ( ! next_target.seen_S)
					break;
				debug_flags = next_target.S;
				break;
      #endif /* DEBUG */

      case 112:
        //? --- M112: Emergency Stop ---
        //?
        //? Example: M112
        //?
        //? Any moves in progress are immediately terminated, then the printer
        //? shuts down. All motors and heaters are turned off. Only way to
        //? restart is to press the reset button on the master microcontroller.
        //? See also M0.
        //?
        timer_stop();
        queue_flush();
        power_off();
        cli();
        for (;;)
          wd_reset();
        break;

			case 114:
				//? --- M114: Get Current Position ---
				//?
				//? Example: M114
				//?
				//? This causes the RepRap machine to report its current X, Y, Z and E coordinates to the host.
				//?
				//? For example, the machine returns a string such as:
				//?
				//? <tt>ok C: X:0.00 Y:0.00 Z:0.00 E:0.00</tt>
				//?
				#ifdef ENFORCE_ORDER
					// wait for all moves to complete
					queue_wait();
				#endif
				update_current_position();
				sersendf_P(PSTR("X:%lq,Y:%lq,Z:%lq,E:%lq,F:%lu\n"),
                        current_position.axis[X], current_position.axis[Y],
                        current_position.axis[Z], current_position.axis[E],
				                current_position.F);

        if (mb_tail_dda != NULL) {
          if (DEBUG_POSITION && (debug_flags & DEBUG_POSITION)) {
            sersendf_P(PSTR("Endpoint: X:%ld,Y:%ld,Z:%ld,E:%ld,F:%lu,c:%lu}\n"),
                       mb_tail_dda->endpoint.axis[X],
                       mb_tail_dda->endpoint.axis[Y],
                       mb_tail_dda->endpoint.axis[Z],
                       mb_tail_dda->endpoint.axis[E],
                       mb_tail_dda->endpoint.F,
                       #ifdef ACCELERATION_REPRAP
                         mb_tail_dda->end_c
                       #else
                         mb_tail_dda->c
                       #endif
            );
          }
          print_queue();
        }

				break;

			case 115:
				//? --- M115: Get Firmware Version and Capabilities ---
				//?
				//? Example: M115
				//?
				//? Request the Firmware Version and Capabilities of the current microcontroller
				//? The details are returned to the host computer as key:value pairs separated by spaces and terminated with a linefeed.
				//?
				//? sample data from firmware:
				//?  FIRMWARE_NAME:Teacup FIRMWARE_URL:http://github.com/traumflug/Teacup_Firmware/ PROTOCOL_VERSION:1.0 MACHINE_TYPE:Mendel EXTRUDER_COUNT:1 TEMP_SENSOR_COUNT:1 HEATER_COUNT:1
				//?

        sersendf_P(PSTR("FIRMWARE_NAME:Teacup "
                        "FIRMWARE_URL:http://github.com/traumflug/Teacup_Firmware/ "
                        "PROTOCOL_VERSION:1.0 MACHINE_TYPE:Mendel EXTRUDER_COUNT:%d "
                        "TEMP_SENSOR_COUNT:%d HEATER_COUNT:%d\n"
                        "cap:AUTOREPORT_TEMP:%d\n"),
                        1, NUM_TEMP_SENSORS, NUM_HEATERS, 1);
				break;

			case 116:
				//? --- M116: Wait ---
				//?
				//? Example: M116
				//?
				//? Wait for temperatures and other slowly-changing variables to arrive at their set values.
        temp_set_wait();
				break;

      case 119:
        //? --- M119: report endstop status ---
        //? Report the current status of the endstops configured in the
        //? firmware to the host.
        power_on();
        endstops_on();
        delay_ms(10); // allow the signal to stabilize
        {
          #if ! (defined(X_MIN_PIN) || defined(X_MAX_PIN) || \
                 defined(Y_MIN_PIN) || defined(Y_MAX_PIN) || \
                 defined(Z_MIN_PIN) || defined(Z_MAX_PIN))
            serial_writestr_P(PSTR("No endstops defined."));
          #else
            const char* const open = PSTR("open ");
            const char* const triggered = PSTR("triggered ");
          #endif

          #if defined(X_MIN_PIN)
            serial_writestr_P(PSTR("x_min:"));
            x_min() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
          #if defined(X_MAX_PIN)
            serial_writestr_P(PSTR("x_max:"));
            x_max() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
          #if defined(Y_MIN_PIN)
            serial_writestr_P(PSTR("y_min:"));
            y_min() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
          #if defined(Y_MAX_PIN)
            serial_writestr_P(PSTR("y_max:"));
            y_max() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
          #if defined(Z_MIN_PIN)
            serial_writestr_P(PSTR("z_min:"));
            z_min() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
          #if defined(Z_MAX_PIN)
            serial_writestr_P(PSTR("z_max:"));
            z_max() ? serial_writestr_P(triggered) : serial_writestr_P(open);
          #endif
        }
        endstops_off();
        serial_writechar('\n');
        break;

      #ifdef EECONFIG
			case 130:
				//? --- M130: heater P factor ---
				//? Undocumented.
			  	//  P factor in counts per degreeC of error
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				if (next_target.seen_S)
					pid_set_p(next_target.P, next_target.S);
				break;

			case 131:
				//? --- M131: heater I factor ---
				//? Undocumented.
			  	// I factor in counts per C*s of integrated error
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				if (next_target.seen_S)
					pid_set_i(next_target.P, next_target.S);
				break;

			case 132:
				//? --- M132: heater D factor ---
				//? Undocumented.
			  	// D factor in counts per degreesC/second
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				if (next_target.seen_S)
					pid_set_d(next_target.P, next_target.S);
				break;

			case 133:
				//? --- M133: heater I limit ---
				//? Undocumented.
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				if (next_target.seen_S)
					pid_set_i_limit(next_target.P, next_target.S);
				break;

			case 134:
				//? --- M134: save PID settings to eeprom ---
				//? Undocumented.
				heater_save_settings();
				break;
      #endif /* EECONFIG */

      #ifdef DEBUG
			case 136:
				//? --- M136: PRINT PID settings to host ---
				//? Undocumented.
				//? This comand is only available in DEBUG builds.
        if ( ! next_target.seen_P)
          #ifdef HEATER_EXTRUDER
            next_target.P = HEATER_EXTRUDER;
          #else
            next_target.P = 0;
          #endif
				heater_print(next_target.P);
				break;
      #endif /* DEBUG */

			case 140:
				//? --- M140: Set heated bed temperature ---
				//? Undocumented.
				#ifdef	HEATER_BED
					if ( ! next_target.seen_S)
						break;
					temp_set(HEATER_BED, next_target.S);
				#endif
				break;

      case 155:
        //? --- M155: Report Temperature(s) Periodically ---
        //?
        //? Example: M155 Sn
        //?
        //? turns on periodic reporting of the temperatures of the current
        //? extruder and the build base in degrees Celsius. The reporting
        //? interval is given in seconds as the S parameter. Use S0 to disable
        //? periodic temperature reporting. The reporting format is the same
        //? as for M105, except there is no "ok" at the start of each report.
        //? For example, the line sent to the host periodically looks like
        //?
        //? <tt>T:201 B:117</tt>
        //?
        //? Teacup supports an optional P parameter as a zero-based temperature
        //? sensor index to address.
        //?

        // S<period-seconds> is required
        if ( ! next_target.seen_S)
          break;
        #ifdef ENFORCE_ORDER
          queue_wait();
        #endif
        if ( ! next_target.seen_P)
          next_target.P = TEMP_SENSOR_none;
        temp_periodic_config(next_target.S, next_target.P);
        break;

      case 220:
        //? --- M220: Set speed factor override percentage ---
        if ( ! next_target.seen_S)
          break;
        // Scale 100% = 256
        next_target.target.f_multiplier = (next_target.S * 64 + 12) / 25;
        break;

      case 221:
        //? --- M221: Control the extruders flow ---
        if ( ! next_target.seen_S)
          break;
        // Scale 100% = 256
        next_target.target.e_multiplier = (next_target.S * 64 + 12) / 25;
        break;

      #ifdef DEBUG
			case 240:
				//? --- M240: echo off ---
				//? Disable echo.
				//? This command is only available in DEBUG builds.
				debug_flags &= ~DEBUG_ECHO;
				serial_writestr_P(PSTR("Echo off\n"));
				break;

			case 241:
				//? --- M241: echo on ---
				//? Enable echo.
				//? This command is only available in DEBUG builds.
				debug_flags |= DEBUG_ECHO;
				serial_writestr_P(PSTR("Echo on\n"));
				break;
      #endif /* DEBUG */

				// unknown mcode: spit an error
			default:
				sersendf_P(PSTR("E: Bad M-code %d\n"), next_target.M);
		} // switch (next_target.M)
	} // else if (next_target.seen_M)
} // process_gcode_command()