Talk to the SMuFF

Deviations from the standard GCodes

Some of the GCodes differ slightly from the standard and have been adopted for the SMuFF for convenience reasons.

G0

moves the given axis to the according tool position, i.e. G0 Y3 moves the Revolver into position for tool 3. Only X and Y axes can be addressed by G0.

G1

moves the axis given into the according position in steps (ticks) or, if the parameter T is omitted, in millimetres. Additionally, you may apply the F parameter to override the configured moving speed, i.e.:
G1 X100 F450 - moves the Selector 100 mm with a speed of 450 mm/s

G12

is being used to control a wiper servo (SERVO1). This GCode accepts a list of parameters which are:

• Sn the speed in ms for moving the servo back and forth (default: n = 200)

• In the minimum position in degrees of the servo while wiping (default: n = 20)

• Jn the maximum position in degrees of the servo while wiping (default: n = 45)

• Pn the resting position in degrees of the servo (default: n = 100)

• Rn the number of repeats or movements between min. and max. position (default: n = 0)

So, in order to use wiping, simply send at least a G12 R10 command or put the according sequence into the SMUFF.CFG file - then a simple G12 will do the job.

M17

switches the relay board from I (internal) to E (external) state, whereas internal means to the N.O. and external to the N.C. terminals. For further details on this topic read this.

M98

will execute (run) a test script located on the SD-Card. The name of the script has to be passed as a parameter in the format P"name".

M119

does not only report the endstop status but can also be utilized to set the status of the Feeder endstop (Z) internally, which is needed in case you have set the ExternalControl parameter to true in the configuration file.

M201

will set the acceleration value for the given stepper (X/Y/Z). It's the same value as stored in SMUFF.CFG.

M203

will set the max. speed value for the given stepper (X/Y/Z). If you apply an additional D parameter, you're able to modify the step delay if necessary. This is the same value as stored in SMUFF.CFG.

M205

is used to setup parameters that are usually defined in SMUFF.CFG but not accessible through GCode commands. The format is:
M205 P"adv_param" Sn [ X | Y | Z ]
whereas S represents the set command of value n and adv_param correlates to the SMUFF.CFG parameter names must be one of the following:

• ToolCount

• ToolSpacing

• BowdenLength

• InsertLength

• ReinforceLength

• SelectorDist

• HomeAfterFeed

• ResetBeforeFeed

• EmulatePrusa

• UseServo

• ServoOffPos

• ServoOnPos

• WipeSequence

• StepsPerMillimeter - requires axis X | Z

• StepsPerRevolution

• MenuAutoClose

• PowerSaveTimeout

• SendActionCmds

• BacklightColor

• HasPanelDue

• EncoderTicks

• SendPeriodicalStats

• SharedStepper

• DuetLaser

• InvertDir - requires axis X | Y | Z

• EndstopTrigger - requires axis X | Y | Z

• Power - requires axis X | Y | Z

• RSense - requires axis X | Y | Z

• Mode - requires axis X | Y | Z

• Microsteps - requires axis X | Y | Z

• Stall - requires axis X | Y | Z

• CoolStepMin - requires axis X | Y | Z

• CoolStepMax - requires axis X | Y | Z

• CoolStepDown - requires axis X | Y | Z

• DriverAddress - requires axis X | Y | Z

• TOff - requires axis X | Y | Z

• MaxStallCount - requires axis X | Y | Z

• StopOnStall - requires axis X | Y | Z

Parameters with [ X | Y | Z ] require the axis letter as an additional information which item (axis / stepper driver) to address.
For WipeSequence the S parameter has to be a string and hence encapsulated in quotes ("). To check the current settings, use the M503 GCode command.
After setting one or more of these parameters, it's recommended to save them onto the SD-Card using the M500 GCode command. Restart the SMuFF to get the new settings being initialized correctly.

M280

is the Servo Position command and has got some special parameters:

• Pn is the servo index (0 = Wiper servo, 1 = Lid servo)

• Sn is the desired servo position (0-180 deg)

• In is the minimum PWM frequency (default: n = 800 depicts 0 deg.)

• Jn is the maximum PWM frequency (default: n = 2400 depicts 180 deg.)

• Fn is the desired servo position in microseconds (800-2400 uS)

• Rn is used as shortcut to open / close the Lid servo (n: 0 = open, 1 = close)

An additional parameter "T" let's you spin the servo from 0 deg. to 180 deg. automatically. This way you can test the servo position settings easily.

M300

is being used to play a tone or a tune on the buzzer. Parameters are:

• Sn is the frequency for a single tone

• Pn is the duration for a single tone

• T"..." is being used to play a tune in the format: F{frequency}D{duration}P{pause}. The dot (.) plays the tone and must not be omitted. Pause may be omitted. You're allowed to pass a string with a max. length of 500 characters for your tune.

• F"..." is being used to play a tune file on the SD-Card, whereas the "..." mark the name of the file (usually xxx.dat).

M503

is used to print out the current configuration values. In contrast to a 3D printer, the printout is in the same format as the configuration file (SMUFF.CFG).

M906

is used to set the TMC RMS current. In addition to the X, Y and Z parameters, you may also use the R and H parameters to set the IRUN (R) and IHOLD (H) values along with this command, whereas the value range of those parameters is 0...31, just as specified in the TMC2209 datasheet .

M914

sets the stall threshold on the TMC2209 stepper drivers. In contrast to Marlin, you also have the option to set the CoolStep threshold using parameter C and the MaxStallCount value using the T parameter for the given axes (X, Y, Z).

M2000 and M2001

are additional GCodes for the SMuFF and you won't find those in the GCode standard. They're used to convert text into a decimal string or vice versa. This commands were used on the Duet3D controller board for the communication over the I2C channel and got obsolete by now.

Prusa MMU2 emulation mode

In this mode, the GCode interpreter additionally will recognize the following commands:

• S Init command (S0-S3)

• P Get FINDA status (P0)

• C Push filament into extruder (C0)

• L Load filament (Lx)

• U Unload filament (U0)

• E Eject filament (Ex)

• K Cut filament (no function) (Kx)

• X Reset (X0)

• F Set filament type (no function) (F0)

• R Recover from Eject (no function) (R0)

• W Wait for user to press button (W0)

The "no function" in the description above means: There's no code behind but the SMuFF will respond with "ok" anyway.

The commands shown here, were taken from the Prusa MMU-Control source code, function process_commands.

Parser behavior

The SMuFF GCode parser eliminates all spaces while parsing, except text in quotes ("). It will also convert all characters received into upper case characters, except text in quotes (") and will recognize and handle backspace characters correctly (in case you key in GCodes directly).

Hence, you don't necessarily have to put spaces into your commands - means "T0 S1" or "t0 S1" will behave the same as "T0S1".

Keep in mind: If you want to send a User Message (M117), you have to enclose your message within quotes, otherwise it'll get upper cased and spaces are being removed.