DO NOT USE THIS ON YOUR MACHINE UNTIL FURTHER NOTICE!!!
===========================================
This RepRap firmware is a mashup between <ahref="https://github.com/kliment/Sprinter">Sprinter</a>, <ahref="https://github.com/simen/grbl/tree">grbl</a> and many original parts.
Derived from Sprinter and Grbl by Erik van der Zalm.
The default baudrate is 250000. This baudrate has less jitter and hence errors than the usual 115200 baud, but is less supported by drivers and host-environments.
This can now be performed by the AutoTemp function
By calling M109 S<mintemp> T<maxtemp> F<factor> you enter the autotemp mode.
You can leave it by calling M109 without any F.
If active, the maximal extruder stepper rate of all buffered moves will be calculated, and named "maxerate" [steps/sec].
The wanted temperature then will be set to t=tempmin+factor*maxerate, while being limited between tempmin and tempmax.
If the target temperature is set manually or by gcode to a value less then tempmin, it will be kept without change.
Ideally, your gcode can be completely free of temperature controls, apart from a M109 S T F in the start.gcode, and a M109 S0 in the end.gcode.
EEPROM:
If you know your PID values, the acceleration and max-velocities of your unique machine, you can set them, and finally store them in the EEPROM.
After each reboot, it will magically load them from EEPROM, independent what your Configuration.h says.
LCD Menu:
If your hardware supports it, you can build yourself a LCD-CardReader+Click+encoder combination. It will enable you to realtime tune temperatures,
accelerations, velocities, flow rates, select and print files from the SD card, preheat, disable the steppers, and do other fancy stuff.
One working hardware is documented here: http://www.thingiverse.com/thing:12663
Also, with just a 20x4 or 16x2 display, useful data is shown.
SD card folders:
If you have an SD card reader attached to your controller, also folders work now. Listing the files in pronterface will show "/path/subpath/file.g".
You can write to file in a subfolder by specifying a similar text using small letters in the path.
Also, backup copies of various operating systems are hidden, as well as files not ending with ".g".
Endstop trigger reporting:
If an endstop is hit while moving towards the endstop, the location at which the firmware thinks that the endstop was triggered is outputed on the serial port.
This is useful, because the user gets a warning message.
However, also tools like QTMarlin can use this for finding acceptable combinations of velocity+acceleration.
Coding paradigm:
Not relevant from a user side, but Marlin was split into thematic junks, and has tried to partially enforced private variables.
This is intended to make it clearer, what interacts which what, and leads to a higher level of modularization.
We think that this is a useful prestep for porting this firmware to e.g. an ARM platform in the future.
A lot of RAM (with enabled LCD ~2200 bytes) was saved by storing char []="some message" in Program memory.
In the serial communication, a #define based level of abstraction was enforced, so that it is clear that
some transfer is information (usually beginning with "echo:"), an error "error:", or just normal protocol,
necessary for backwards compatibility.
Interrupt based temperature measurements:
An interrupt is used to manage ADC conversions, and enforce checking for critical temperatures.
This leads to less blocking in the heater management routine.
Non-standard M-Codes, different to an old version of sprinter:
G2 - CW ARC
G3 - CCW ARC
General:
M17 - Enable/Power all stepper motors
M18 - Disable all stepper motors; same as M84
M30 - Print time since last M109 or SD card start to serial
M42 - Change pin status via gcode
M80 - Turn on Power Supply
M81 - Turn off Power Supply
M114 - Output current position to serial port
M119 - Output Endstop status to serial port
Movement variables:
M202 - Set max acceleration in units/s^2 for travel moves (M202 X1000 Y1000) Unused in Marlin!!
M203 - Set maximum feedrate that your machine can sustain (M203 X200 Y200 Z300 E10000) in mm/sec
M204 - Set default acceleration: S normal moves T filament only moves (M204 S3000 T7000) im mm/sec^2 also sets minimum segment time in ms (B20000) to prevent buffer underruns and M20 minimum feedrate
M220 - set build speed factor override percentage S:factor in percent ; aka "realtime tuneing in the gcode"
M301 - Set PID parameters P I and D
M400 - Finish all moves
Advance:
M200 - Set filament diameter for advance
M205 - advanced settings: minimum travel speed S=while printing T=travel only, B=minimum segment time X= maximum xy jerk, Z=maximum Z jerk
EEPROM:
M500 - stores paramters in EEPROM
M501 - reads parameters from EEPROM (if you need reset them after you changed them temporarily).
M502 - reverts to the default "factory settings". You still need to store them in EEPROM afterwards if you want to.
