Introduction

3📅Update: 2020/09/04
DexArm is developed based on the world's leading open-source project Marlin, the DexArm firmware is completely open-source, and its control commands (G-code) are compatible with Marlin. Please visit GitHub for more details of our firmware project. 
G-code commands are the general control commands for CNC machines, 3D printers, etc. It is composed of ASCII strings, such as G1 F2000 X0 Y300 Z0, G-code commands usually uses \n as the sending end character.
In Marlin, the slave device will reply ok after receiving the G-code commands, the host computer then can send the next commands after receiving the ok. In DexArm SDK (pydexarm - download below👇), we have encapsulated this sending and receiving mechanism and make it convenient for users to use.
pydexarm_V1.0.zip
7KB
Binary
DexArm Python SDK V1.0
Communication Parameters
Baud rate: 115200
Data bits: 8
Stop bits: 1
Parity: None
Flow control: None
Commands end with CR+LF, hereinafter referred to as 0D0A.
When the slave device receives a command, if the command is correct, it returns "ok"; if not, it returns "unknown command".
Initialization
After the host computer is connected to the robot arm, please send the command  M1112  first to move the arm to the HOME (X0 Y300 Z0) position.
Basic Motion Control Commands
M1112
Reset to the HOME position (X0 Y300 Z0)
Don't mix up with the M112 Emergency stop command. 
M1111
Move to the recalibration position
M1113
Execute M1111 first, then M1112
G0 - Rapid Movement
X - Movement distance of X-axis in mm, accuracy 0.1mm
Y - Movement distance of Y-axis in mm, accuracy 0.1mm
Z - Movement distance of Z-axis in mm, accuracy 0.1mm
E - Movement distance of E-axis in mm, accuracy 0.1mm
F - Movement speed in mm/s, default speed is 40mm/s
G1 - Linear Movement
X - Movement distance of X-axis in mm, accuracy 0.1mm
Y - Movement distance of Y-axis in mm, accuracy 0.1mm
Z - Movement distance of Z-axis in mm, accuracy 0.1mm
E - Movement distance of E-axis in mm, accuracy 0.1mm
F - Movement speed in mm/s, default speed is 40mm/s
G90 - Absolute Positioning
Under this command, G0 and G1 movement is in absolute mode. 
For example, the current position is X300 Y0 Z0, sending G0 X310, the Arm moves to X310 Y0 Z0. 
G91 - Relative Positioning
Under this command, G0 and G1 movement is in relative mode. 
For example, the current position is X300 Y0 Z0, sending G0 X10, the Arm moves to X310 Y0 Z0. 
G92 X0 Y0 Z0 E0 
Set the current position as the Work Origin
G92.1 - Reset G92 Command
For example, if the arm is currently at X300 Y0 Z0 E0, sending G92 X0 Y0 Z0 E0 will set the current position as the Work Origin. Sending M114 to read position, you will get X0 Y0 Z0 E0, the arm is working under the Work Object Coordinate System. Sending G92.1 will reset G92 command, and the arm will reset to the original coordinate system.
G4 - Dwell Command
P500 - dwell for 500ms
S10 - dwell for 10s
Return Values
M2010 - Return firmware version
M2011 - Return hardware version
M503 - Return device status info
M115 - Return Marlin firmware info
M897 - Whether the arm moved to the target position
M1004 - Check air pump box status
Air pump
In - pump in
Out - pump in
Neutral - release air
Off - turn off 
M2014 - check the status of the conveyor belt, including moving direction and speed.
Forward xx mm/s
Backward xx mm/s
Stop
M6 - check the status of laser module 
On - the laser is on 
Off - the laser is off
M18 - motor deactivation command. After sending M18, the motor will go into deactivation and can be manually adjusted for recalibration or the teach & Play function.
Motion Commands
M114 - return the current position value, in mm. If the rotary module is connected, it also returns the R absolute angle value. 
M204 - read and set robot arm moving acceleration value. The default setting is M204 P200 R60 T200. 
When it is without any parameters, it reads the acceleration value. 
P - printing acceleration value. 
R - returning acceleration value. 
T - idle stroke acceleration value. 
M889 - Read magnet encoder value and set the initial calibration position. 
X Y Z - set magnet encoder value of current position for recalibration.
M890 - get the magnet encoder position readings. 
M891 
X Y - set the current XY slope value, usually used in 3D printing leveling.
M892 - read the current XY slope value
M893 - refresh the magnet encode value from the sensor
M894 - set a target value of the magnet encoder
X - the X-axis encoder value of target position, range 
Y - the Y-axis encoder value of target position, range 
Z - the Z-axis encoder value of target position, range 
M895 
read the magnet encode values from the sensors and then convert it into actual coordinate values, displayed in the Cartesian coordinate system, in mm. 
for teach & play function
M81 - turn off the fan, heating or other functions.
M410 - stop the arm movement quickly, send G0 and G1 commands to continue the movement.
M112 - emergency stop command, the arm will not respond to any commands. Need to reboot the arm for more action. 
Basic Controls
Motion Mode
M2000
Switch G0 to linear movement. 
M2001
Switch G0 to rapid movement. 
Basic Movement commands
G91: enter relative mode.
G0 X1: move +1mm on the X-axis. 
G90: enter absolute mode.
​
Front-end Module Switch
M880
P0 - set the front-end module as the pen holder module
P1 - set the front-end module as the laser module
P2 - set the front-end module as the pneumatic module
P3 - set the front-end module as the 3D printing module
P4 - set the front-end module as the rotary module
P10 - turn on the safety enclosure laser protection
P11 - turn off the safety enclosure laser protection
P13 - check safety enclosure door status
No Parameter/send M880 directly - check the current module
Each time when you enter a module function interface, you need to send the module setting command. 
Writing/Drawing
Process of G-Code files: 
1.send by code line, each line ends with 0D0A
2.only sending the next code when it receives the "ok" return value from the server
3.the code line starting with";" will be automatically filtered by the host computer, and will not be sent to the server
4.Pause/Resume, corresponding to pause or continue sending commands in the host computer.
Laser Module
M3 - command to turn on laser
Parameters
1.S corresponds to the laser power duty cycle, the range is 0-255. Special definition: when it is S1, the laser power is very low, suitable for laser engraving borders.
2.Example: M3 S10 - turn on the laser with a duty cycle of 10. 
M5 - Turn off the laser module.
M6 - Return to laser on/off status. 
Pneumatic Module
M1000 - air pump box pump in/soft grip start gripping
M1001 - air pump box pump out/soft grip start opening 
M1002 - air pump box/soft grip return to original status
M1003 - all air pump boxes stop working 
Teach & Play
Teach: Send M893, the arm returns M894 + the magnet encoder value of 3-axises, the software or touch screen saves the corresponding data.
Replay: Resend the saved information and the arm will repeat the previously recorded movement.
3D Printing
M104 Sxx - set the extrusion head temperature, during which the motion command is possible. 
Sxx - target temperature, accuracy 1°C
Example: M104 S200 - Set the extrusion head target temperature to 200°C.
M105 - get the current extrusion head temperature
M108 - get the extruder speed
M109 Sxx - Set the extruder target temperature xx and wait for the temperature to rise. No command will be executed during this period. The server unit will return the current temperature in real-time. 
Sxx - target temperature, precision 1°C 
Example: M109 S200 - Sets the extrusion head target temperature to 200°C and wait for the temperature to rise.
M106 Sxx - Set fan speed xx
M107 - turn off the fan
M130 - Set heater bar PID P value
M131 - Set the heater bar PID I value
M132 - Set heater bar PID D value
G0 EXXX FXXX - Extrude E length at F speed
Conveyor Belt 
M2012 - control the rotation of the conveyor belt
Parameters: F speed (in mm/min), D direction (0 is clockwise, 1 is counterclockwise)
For example:
M2012 F1000 D0 - rotate clockwise in 1000mm/min speed.
M2012 F200 D1 - rotate counterclockwise in 200mm/min speed.
M2013 - stop the conveyor belt
M2014 - check the status of the conveyor belt
M1115 - M1119 - return the color recognition sensor data. For the scratch color recognition function and other demos. Parameters:
1115: item - means there is an item. 
1116: red - indicates a red block. 
1117: green - indicates a red block. 
1118: blue - indicates a blue block. 
1119: yellow - Indicates a yello block.
Sliding Rail 
M2005 - E axis return to the home point. With the locked rotor test function of TMC2209, it drives the slide back to the home point twice, when the TMC is pushed to the limit, the slide is returned to the home point successfully. 
Parameters: XYZE must be fully set, otherwise use the default values (30, 10, 60, 60).
X - HOME maximum speed
Y - HOME lowest speed
Z - the 1st TMC detection threshold value
E - the 2nd TMC detection threshold value
M2006 - check if the return operation is completed. 
M914 - set the sensitivity of TMC blocking for the E-axis.
Rotary Module
M888 P6 - set the offset value and initialize the rotary module
M2100 - initialize the rotary module
M2101 - get the rotary module angle value, control the movement, with 1-degree accuracy. Parameters:
Without parameters: get the absolute angle of the rotary module.
R(relative) - rotate the module by n degrees from the current position, n can be greater than 360.
1.Clockwise rotation n degrees, M2101 Rn 
2.Counterclockwise rotation n degrees, M2101 R-n
P(position) - rotates the rotary joint to an absolute angle n. 
1.M2101 Pn - rotate the module to an absolute angle n, the range of n is 0 - 360.
S - set the module rotates continuously, speed range from 0-100. S0 refers to speed zero(stop). S1 refers to rotation at a low speed, S100 refers to rotation at the highest speed.
clockwise rotation continuously, M2101 Sn 
counterclockwise rotation continuously, M2101 S-n 
M2102 - Upgrade the firmware of the rotary module
Parameter U - Upgrade step number, default is 0. 
0 - no operation
1 - enter boot 
2 - set the file size with the s parameter
3 - receive the file
M2103 - check the current rotary module firmware version
For example, M2103, return Rotary Firmware V1.1.2
Firmware Upgrade
M2002 - enter Bootloader
M2003 - confirm the upgrade, enter Bootloader
Once enter Bootloader, send numbers 1-5 to view device data, send firmware, etc. 
1 - download firmware to the robot arm 
2 - upload firmware from the robot arm 
3 - execute firmware 
4 - enter boot protection mode, no firmware transfer 
5 - print the device firmware and hardware version data. 
M2004 - Cancel upgrade
M2007 - Reboot the device.
Error Report
ERROR 100-199, motion and initialization related, such as M1112
ERROR 200-299, motion and initialization related, 3D printing related, such as heating, temperature, etc.
Error:100, Position Sensor Read Error 
Position sensor error 
Exceed the sensor reading maximum range, such as 65535 
Possible causes: usually 8Pin wire loose, off, or magnetic code board damage
Error:103, Position Sensor Diff Error 
M1112 M1111 sensor DIFF exceeds the maximum angle range 
Possible causes: calibration error, magnet off
Error: 101, 102 Home Error 
Home Error (Axis data). 
Possible causes: wrong magnet, magnet off, motor wire loose, motion out of step, etc.
Error: 203, MINTEMP triggered, system stopped! Heater_ID: 0
When the heating is turned on, the minimum temperature is triggered, usually, the temperature sensor is not inserted, or the temperature sensor is disconnected.
Error: 202, MAXTEMP triggered, system stopped! Heater_ID: 0
the maximum temperature is triggered, usually caused by a broken temperature sensor.
Error:200, Heating failed, system stopped! Heater_ID: 0
No significant temperature change (<2°C) after a certain heating time (20S)
Error: 201, Thermal Runaway, system stopped! Heater_ID: 0
After heating up to the specified temperature, the temperature drops significantly.
Leveling related commands
Set leveling coefficient
M891 Xn Yn
Read leveling coefficient
M891
Magnet encoder related commands
Read current encoder position data
M893
Move to a specific encoder value position
M894 Xn Yn Zn
End effector control commands
Pneumatic module control commands
M1000 - air pump box to pump in
M1001 - air pump box to pump out
M1002 - air pump box to release air
To return to original status when the suction cup/soft gripper is not working.
M1003 - stop air pump box
Laser engraving module control commands
Related control commands M003 M005 
3D printing control commands
​M104​
​M105​
​M108​
​M106​
​M107​
​M109 ​
Accessory control commands
Conveyor belt control commands
set conveyor belt working speed as 2000mm/min, clockwise
M2012 F2000 D0
set conveyor belt working speed as 2000mm/min, counter-clockwise
M2012 F2000 D1
stop conveyor belt
M2013
Reset the touchscreen firmware
Connect the touchscreen to DexArm after sending the following commands:
M5010000
Reset DexArm Settings
Reboot DexArm and enter bootloader
Send commands M2002, M2003 in sequence to enter bootloader mode.
Reboot DexArm commands
M2007
Re-calibrate the initial position
The DexArm HOME position and motion coordinates are based on the initial position. The initial position has been calibrated before leaving the factory. If there is an error in the arm movement, please re-calibrate the initial position according to the following instruction:
1. Adjust the arm to the following position, make sure Axis 1 and Axis 2 is in the maximum position:
2. Send command M889
Advanced commands
[Marlin] G020 - Inch Units
[Marlin] G021 - Millimeter Units
[Marlin] M906 - TMC Motor Current
[Marlin] M500 - Save Settings
[Marlin] M501 - Restore Settings
[Marlin] M502 - Factory Reset
[Marlin] M503 - Report Settings
[Marlin] M082 - E Absolute
[Marlin] M083 - E Relative
[Marlin] M092 - Set Axis Steps-per-unit
[Marlin] M200 - Set Filament Diameter
[Marlin] M400 - Finish Moves
[Marlin] M410 - Quickstop
[Marlin] M504 - Validate EEPROM contents
Safety enclosure wiring changes
Next - ⌨API(G-code)
Marlin Original Commands
Last modified 1mo ago