Firmware for Original Prusa i3 3D printer by PrusaResearch
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Run shell script to build for MK3 and flash with Sli3er.
If you have different printel model, follow step 2.b from Windows build first.
If you wish to flash from Arduino, follow step 2.c from Windows build first.

The script downloads Arduino with our modifications and Rambo board support installed, unpacks it into folder PF-build-env-<version> on the same level, as your Prusa-Firmware folder is located, builds firmware for MK3 using that Arduino in Prusa-Firmware-build folder on the same level as Prusa-Firmware, runs secondary language support scripts. Firmware with secondary language support is generated in lang subfolder. Use firmware.hex for MK3 variant. Use firmware_<lang>.hex for other printers. Don't forget to follow step 2.b first for non-MK3 printers.


1. Development environment preparation

a. install "Arduino Software IDE" for your preferred operating system -> Software->Downloads
it is recommended to use version "1.8.5", as it is used on out build server to produce official builds.
note: in the case of persistent compilation problems, check the version of the currently used C/C++ compiler (GCC) - should be 4.8.1; version can be verified by entering the command
avr-gcc --version
if you are not sure where the file is placed (depends on how "Arduino Software IDE" was installed), you can use the search feature within the file system

note: name collision for "LiquidCrystal" library known from previous versions is now obsolete (so there is no need to delete or rename original file/-s)

b. add (UltiMachine) RAMBo board into the list of Arduino target boards
into text field "Additional Boards Manager URLs"
type location
or you can 'manually' modify the item
at the file "preferences.txt" (this parameter allows you to write a comma-separated list of addresses)
note: you can find location of this file on your disk by following way:
File->Preferences->Settings ("More preferences can be edited in file ...")

than do it
from viewed list select an item "RAMBo" (will probably be labeled as "RepRap Arduino-compatible Mother Board (RAMBo) by UltiMachine"
note: select this item for any variant of board used in printers 'Prusa i3 MKx', that is for RAMBo-mini x.y and EINSy x.y to
'clicking' the item will display the installation button; select choice "1.0.1" from the list(last known version as of the date of issue of this document)
(after installation, the item is labeled as "INSTALLED" and can then be used for target board selection)

c. modify platform.txt to enable float printf support:
add "-Wl,-u,vfprintf -lprintf_flt -lm" to "compiler.c.elf.flags=" before existing flag "-Wl,--gc-sections"
"compiler.c.elf.flags=-w -Os -Wl,-u,vfprintf -lprintf_flt -lm -Wl,--gc-sections"

2. Source code compilation

a. place the source codes corresponding to your printer model obtained from the repository into the selected directory on your disk

b. In the subdirectory "Firmware/variants/" select the configuration file (.h) corresponding to your printer model, make copy named "Configuration_prusa.h" (or make simple renaming) and copy it into "Firmware/" directory.

c. In file "Firmware/config.h" set LANG_MODE to 0.

run "Arduino IDE"; select the file "Firmware.ino" from the subdirectory "Firmware/" at the location, where you placed the source codes
make the desired code customizations; all changes are on your own risk!

select the target board "RAMBo"
note: it is not possible to use any of the variants "Arduino Mega …", even though it is the same MCU

run the compilation

upload the result code into the connected printer

or you can also save the output code to the file (in so called HEX-format) "Firmware.ino.rambo.hex":
and then upload it to the printer using the program "FirmwareUpdater"
note: this file is created in the directory "Firmware/"

3. Automated tests


c++11 compiler e.g. g++ 6.3.1


build system - ninja or gnu make


Create folder where you want to build tests.


cd ..

mkdir Prusa-Firmware-test

Generate build scripts in target folder.


cd Prusa-Firmware-test

cmake -G "Eclipse CDT4 - Ninja" ../Prusa-Firmware

or for DEBUG build:

cmake -G "Eclipse CDT4 - Ninja" -DCMAKE_BUILD_TYPE=Debug ../Prusa-Firmware

Build it.





4. Documentation

run doxygen in Firmware folder