Important information related to BigTreeTech's TFT touchscreen 3D printer controllers
Only the TFTs listed below are currently supported. Trying to install the firmware on a TFT which is not supported can harm the hardware.
BTT TFT
BTT_TFT24_V1.1
BTT_TFT28_V1.0 and V3.0
BTT_TFT35_V1.0, V1.1, V1.2, V2.0, V3.0, E3_V3.0 and B1_V3.0
BTT_TFT43_V3.0
BTT_TFT50_V3.0
BTT_TFT70_V3.0
BTT GD TFT
BTT_GD_TFT24_V1.1
BTT_GD_TFT35_V2.0, V3.0, E3_V3.0 and B1_V3.0
BTT_GD_TFT43_V3.0
BTT_GD_TFT50_V3.0
BTT_GD_TFT70_V3.0
MKS TFT
MKS_TFT28_V3.0 and V4.0
MKS_TFT28_NEW_GENIUS
MKS_TFT32_V1.3 and V1.4
MKS_TFT32L_V3.0
MKS_TFT35_V1.0
MKS GD TFT
MKS_GD_TFT28_V1.2-4 (V1.2 and V1.4)
WARNING: BTT does not officially provide MKS TFT hardware support. MKS TFT is maintained by open source contributors and BTT does not bear any risk of MKS TFT hardware using this firmware.
Firmware source: https://github.com/bigtreetech/BIGTREETECH-TouchScreenFirmware
Main branch: Master
In the Master branch you will find:
IMPORTANT NOTE: The Master branch is currently the ONLY branch in the project to be used. The other currently existing branches develop and release-xx.27 are outdated and MUST NOT be used.
Minimum Marlin firmware version: 2.1.1
Distribution date: 2022-09-22
Firmware source: https://github.com/MarlinFirmware/Marlin/releases
To use all the features and functionalities supported by the TFT, the following options must be enabled in Marlin firmware.
General options which MUST be always activated:
EEPROM_SETTINGS
(in Configuration.h)
BABYSTEPPING
(in Configuration_adv.h)
AUTO_REPORT_TEMPERATURES
(in Configuration_adv.h)
AUTO_REPORT_POSITION
(in Configuration_adv.h)
EXTENDED_CAPABILITIES_REPORT
(in Configuration_adv.h)
M115_GEOMETRY_REPORT
(in Configuration_adv.h)
M114_DETAIL
(in Configuration_adv.h)
REPORT_FAN_CHANGE
(in Configuration_adv.h)
Options to support printing from onboard media:
SDSUPPORT
(in Configuration.h)
LONG_FILENAME_HOST_SUPPORT
(in Configuration_adv.h)
AUTO_REPORT_SD_STATUS
(in Configuration_adv.h)
SDCARD_CONNECTION ONBOARD
(in Configuration_adv.h)
Options to support dialog with host:
EMERGENCY_PARSER
(in Configuration_adv.h)
SERIAL_FLOAT_PRECISION 4
(in Configuration_adv.h)
HOST_ACTION_COMMANDS
(in Configuration_adv.h)
HOST_PROMPT_SUPPORT
(in Configuration_adv.h)
HOST_STATUS_NOTIFICATIONS
(in Configuration_adv.h)
Options to support M73 with host:
Options to support dialog with host
(as pre requisite)
SET_PROGRESS_MANUALLY
(in Configuration_adv.h)
M73_REPORT
(in Configuration_adv.h)
Options to support ADVANCED_OK with host:
ADVANCED_OK
(in Configuration_adv.h)
Options to support M600 with host & (Un)Load menu:
Options to support dialog with host
(as pre requisite)
NOZZLE_PARK_FEATURE
(in Configuration.h)
ADVANCED_PAUSE_FEATURE
(in Configuration_adv.h)
PARK_HEAD_ON_PAUSE
(in Configuration_adv.h)
FILAMENT_LOAD_UNLOAD_GCODES
(in Configuration_adv.h)
Options to fully support Bed Leveling menu:
Z_MIN_PROBE_REPEATABILITY_TEST
(in Configuration.h)
G26_MESH_VALIDATION
(in Configuration.h)
Z_STEPPER_AUTO_ALIGN
(in Configuration_adv.h)
In order to use the Touch Mode on your screen:
In case one of the three points above is not properly done, the message:
No printer attached!
will be shown at the top of the screen. This is because the TFT can not "see" the mainboard through the serial cable.
On TFT firmware, the baudrate can be changed in two ways:
serial_port
in config.ini
file with the proper baudrate (e.g. serial_port:P1:6
for baudrate 115200). Please, see Configuration section for configuring config.ini
fileIn order to use the Marlin Mode (emulation mode) on your screen:
REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
is activated in Configuration.h
and that all other controllers are Deactivated (especially CR10_STOCKDISPLAY
).CR10_STOCKDISPLAY
is activated in Configuration.h
and that all other controllers are Deactivated (especially REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
).
Status Screen DISABLED | Status Screen ENABLED |
---|---|
If status_screen:0 is not defined in config.ini, define: # UI Settings # Status Screen # Select the Main Screen flavour # Options: [disable: 0, enable: 1] status_screen:0 |
If status_screen:1 is not defined in config.ini, define: # UI Settings # Status Screen # Select the Main Screen flavour # Options: [disable: 0, enable: 1] status_screen:1 |
Unified Menu Theme | The Round Miracle Theme by Acenotass |
---|---|
Use firmware, icons, and fonts from the Copy to SD Card root directory to update - Unified Menu Material theme folder |
Use firmware, icons, and fonts from the Copy to SD Card root directory to update - The Round Miracle theme folder |
Hybrid Red Material Theme by AntoszHUN | Hybrid Mono Material Theme by bepstein111 |
---|---|
Use firmware, icons, and fonts from the Copy to SD Card root directory to update - Hybrid Red Menu Material theme folder |
Use firmware, icons, and fonts from the Copy to SD Card root directory to update - Hybrid Mono Menu Material theme folder |
Rep Rap Firmware Dark Theme by xPew | |
---|---|
Use firmware, icons, and fonts from the Copy to SD Card root directory to update - Rep Rap Firmware Dark theme folder |
The TFT firmware update process is based on the following stages:
The following sections provide all the resources needed for the firmware update (up to four kinds of resources).
Precompiled firmwares are available on Copy to SD Card root directory to update
folder.
For BTT TFTs, the firmwares use the naming convention BIGTREE_TFT*_V*.*.*.x.bin
.
For BTT GD TFTs, the firmwares use the naming convention BIGTREE_GD_TFT*_V*.*.*.x.bin
For MKS TFTs:
MKS_TFT*_V*.*.*.x.bin
MKS_TFT28_V4.0.27.x.bin
) MUST be renamed to MKSTFT*.bin
(e.g. MKSTFT28.bin
, MKSTFT35.bin
etc.) in order it can be recognized and installed by the TFTFor MKS GD TFTs:
For MKS TFT28 mounting GD32 MCU (GigaDevice MCU) (like the newest version of Genious Pro), you need to:
MKS_GD_TFT28_V1_2_4.27.x.bin
) to MKSTFT28EVO.bin
MKSTFT28.bin
MKS_FONT
and MKS_PIC
For example, for BTT TFT35 V3 select:
BIGTREE_TFT35_V3.0.27.x.bin
where:
BIGTREE_TFT35
: ModelV3.0
: Hardware version27.x
: Software versionNOTE:
For BTT TFT35, there are currently three different kinds of firmware available:
So, make sure to use the firmware matching your TFT screen.
Themes are available on Copy to SD Card root directory to update
folder.
The root folder for fonts and icons is TFT*
, where *
is the size of the TFT (e.g. TFT24
, TFT35
, TFT50
etc). Fonts and icons folder structure:
TFT*/font
: Includes the fonts in .fon format and a readme.mdTFT*/bmp
: Includes the icons in .bmp format and a readme.mdFor MKS TFT32, the TFT28
folder has to be used and MUST be renamed to TFT32
in order it can be recognized and installed by the TFT.
Templates for configuration file are available on Copy to SD Card root directory to update
folder.
The configuration file is named config.ini
.
NOTE: RepRap firmware users have to make their changes using the config_rrf.ini
template file and renaming it to config.ini
.
Optional language files are available on Copy to SD Card root directory to update/Language Packs
folder.
Language files use the naming convention language_*.ini
(e.g. language_it.ini
).
The firmware configuration can be modified by changing the config.ini
(or the renamed config_rrf.ini
) file using a simple text editor (make sure to use UTF encoding).
A configuration can be uploaded without the need to upload the firmware or the TFT folder again, as long as the firmware and the configuration file are from the same version (see Configuration Update).
NOTE: RepRap firmware users have to make their changes using the config_rrf.ini
template file and renaming it to config.ini
.
To edit the config.ini
file, follow the instructions here: Detailed Instructions.
NOTE: For devices with USB flash drive support, it is possible to update the icons, fonts, config and the language files from a USB flash drive in the same way it is done through an SD card. However, the firmware can only be updated using an SD card.
The following steps are needed in order to install the firmware:
Copy the precompiled BIGTREE_TFT*_V*.*.*.bin
or your self compiled firmware, plus the TFT*
folder of your preferred theme along with config.ini
to the root of a blank SD card not greater than 8GB and formatted as FAT32:
Optionally, copy one or more language_*.ini
file(s) onto the SD card. Doing so, it will allow you to switch between English and the uploaded language(s) from the Language menu present in the TFT firmware. We recommend to upload the minimum amount of languages to keep the memory usage low. The language_*.ini
file can be edited to change the text shown on the TFT:
Place the SD card with BIGTREE_TFT*_V*.*.*.bin
, the TFT*
folder, config.ini
and the optional language_*.ini
file(s) into the TFT's SD card reader and reset your TFT (or optionally - power cycle your printer) to start the update process:
⚠️ Failing to update your icons & fonts will result in missing icons and/or unreadable text ⚠️
Update process shown on TFT screen:
A successful update looks like this on the screen:
... and the name of the elements on the SD card changes to this:
In case one or several parts of the update failed, an error will be shown. Follow the information on the screen to update the missing or outdated elements:
⚠️ Errors during the update can not be ignored and must be solved before using the TFT ⚠️
After the update is done and the files are renamed, it is possible to reuse them again. To do so, change the name of the element(s) to the pre-update name and start the update process again.
After a successful update, the TFT will switch to one of the following menus:
TIP: Format the SD card after the firmware update in case you would like to print from it.
In case major changes have been applied by the installed firmware, a post installation process consisting on touch screen calibration is automatically started.
Please, see Touch Screen Calibration section for completing the process.
Please, see Configuration section for configuring config.ini
file.
NOTES:
In order to update the firmware configuration:
config.ini
file to the root of the SD card. The SD card capacity should be less than or equal to 8GB and formatted as FAT32config.ini
file will be renamed to config.ini.CUR
after updating the configurationThe touch screen calibration process begins showing a white screen with a red dot in the upper right corner and the following text:
Touch Screen Calibration - Please click on the red dot
Once the process is started, to calibrate the touch screen press (with your finger or a stylus):
Repeat the process in case the following message is shown:
Adjustment failed, please try again.
The touch screen calibration process can be forced in two ways:
NOTES:
config.ini
file (see Configuration Update)The hard reset process consists in:
In order to hard reset the firmware:
reset.txt
reset.txt
file to the root of the SD card. The SD card capacity should be less than or equal to 8GB and formatted as FAT32reset.txt
file will be renamed to reset.txt.DONE
after the touch screen calibration process is completedWhen the default hard coded settings are properly configured for a TFT and the TFT's basic function such as surfing on the menus is working, in case of issues the user can opt to apply only a configuration reset (soft reset) instead of an hard reset.
In order to reset to default settings:
Please, see Customization Guides section for detailed information.
platformio.ini
and change the default_envs
to one that matches your TFT model and version:
;BIGTREE_TFT24_V1_1 ;BIGTREE_TFT28_V1_0 ;BIGTREE_TFT28_V3_0 ;BIGTREE_TFT35_V1_0 ;BIGTREE_TFT35_V1_1 ;BIGTREE_TFT35_V1_2 ;BIGTREE_TFT35_V2_0 ;BIGTREE_TFT35_V3_0 ;BIGTREE_TFT35_E3_V3_0 ;BIGTREE_TFT35_B1_V3_0 ;BIGTREE_TFT43_V3_0 ;BIGTREE_TFT50_V3_0 ;BIGTREE_TFT70_V3_0 ;BIGTREE_GD_TFT24_V1_1 ;BIGTREE_GD_TFT35_V2_0 ;BIGTREE_GD_TFT35_V3_0 ;BIGTREE_GD_TFT35_E3_V3_0 ;BIGTREE_GD_TFT35_B1_V3_0 ;BIGTREE_GD_TFT43_V3_0 ;BIGTREE_GD_TFT50_V3_0 ;BIGTREE_GD_TFT70_V3_0 ;MKS_TFT28_V3_0 ;MKS_TFT28_V4_0 ;MKS_TFT28_NEW_GENIUS ;MKS_TFT32_V1_3 ;MKS_TFT32_V1_4 ;MKS_TFT32_V1_4_NOBL ;MKS_TFT32L_V3_0 ;MKS_TFT35_V1_0 ;MKS_GD_TFT28_V1_2_4 [platformio] src_dir = TFT boards_dir = buildroot/boards default_envs = BIGTREE_TFT35_V3_0
Ctrl
+Alt
+B
(Windows) / Ctrl
+Option
+B
(macOS) to compile:
BIGTREE_TFT*_V*.*.*.bin
file will be generated in the hidden .pio\build\BIGTREE_TFT*_V*_*
folder. Follow the update process outlined in the Firmware Update section above to update your TFT to the latest versionTIP: In case there is a problem compiling the TFT firmware try to restart VSC. If this does not help and you are using macOS, delete the packages and platforms folders usually present under the folder /Users/***username***/.platformio/
.
All the precompiled firmwares available on Copy to SD Card root directory to update
folder are compiled to support the standard (horizontal) screen orientation.
In case the TFT needs to be placed with a vertical orientation (e.g. 90°), the firmware needs to be compiled with the portrait mode support and installed following the procedure below:
platformio.ini
;
character) the following line:
; -DPORTRAIT_MODE="_portrait" ; uncomment here to enable Portrait Mode .bin firmware generation
BIGTREE_TFT*_V*.*.*.x_portrait.bin
is created (see the presence of the _portrait suffix)BIGTREE_TFT*_V*.*.*.x.bin
BIGTREE_TFT*_V*.*.*.x.bin
, the TFT*
folder, config.ini
and also reset.txt
(needed to force the screen calibration) into the SD cardIn case the firmware update process failed:
TFT*
folder and config.ini
again (like described above) using a new SD card - 8GB or smaller, FAT32 formattedNOTE: Some uploads worked fine after executing a low level format of the SD card and not a quick format.
In case:
and the reset described above did not help, try the following:
NOTE: With only power supplied, you should be able to navigate through the menus using the touchscreen and even to switch to Marlin Mode (if available). Marlin Mode will not show any interface without a proper EXP connection (see Marlin Mode Setup).
Please, see BIGTREETECH-TouchScreenFirmware/releases section for a complete version history.
OctoPrint, ESP3D, Pronterface etc, connected to a TFT's serial port, can browse files on both the TFT's and mainboard's media devices and start a print that will be handled by the host (TFT or mainboard). The following actions and the related triggering G-codes are currently supported by the TFT fw:
TFT SD | TFT USB | onboard media | |
---|---|---|---|
ACTION | G-CODE | G-CODE | G-CODE |
init media device | M21 <S> <U> |
||
release media device | M22 |
||
list files | M20 SD:<folder path> or M20 S <folder path> Examples: M20 SD: M20 SD:/test M20 S /test |
M20 U:<folder path> or M20 U <folder path> |
M20 |
select file | M23 SD:<file path> or M23 S <file path> Examples: M23 SD:cap.gcode M23 SD:/test/cap2.gcode M23 S /test/cap2.gcode |
M23 U:<file path> or M23 U <file path> |
M23 <file path> |
start/resume print | M24 |
M24 |
M24 |
pause print | M25 |
M25 |
M25 |
pause print and park head | M125 |
M125 |
M125 |
abort print | M524 |
M524 |
M524 |
report print status | M27 [C] |
M27 [C] |
M27 [C] [S<seconds>] |
start file write | M28 SD:<file path> or M28 S <file path> Examples: M28 SD:cap.gcode M28 SD:/test/cap2.gcode M28 S /test/cap2.gcode |
M28 U:<file path> or M28 U <file path> |
M28 [B1] <file path> |
stop file write | M29 |
M29 |
M29 |
delete file | M30 SD:<file path> or M30 S <file path> Examples: M30 SD:cap.gcode M30 SD:/test/cap2.gcode M30 S /test/cap2.gcode |
M30 U:<file path> or M30 U <file path> |
M30 <file path> |
firmware info | M115 TFT |
M115 TFT |
M115 |
play tone | M300 TFT [P<ms>] [S<Hz>] |
M300 TFT [P<ms>] [S<Hz>] |
M300 [P<ms>] [S<Hz>] |
NOTES:
M27 C
) have the same meaning like in Marlin fwOctoPrint, ESP3D, Pronterface etc, connected to a TFT's or mainboard's serial port, can host a print (print handled by the host) and optionally can trigger some actions to the TFT sending specific G-codes. The following actions and the related triggering G-codes are currently supported by the TFT fw:
ACTION | G-CODE |
---|---|
start | M118 P0 A1 action:print_start |
end | M118 P0 A1 action:print_end |
cancel | M118 P0 A1 action:cancel |
pause | M118 P0 A1 action:pause |
resume | M118 P0 A1 action:resume |
remaining time progress | M118 P0 A1 action:notification Time Left <XX>h<YY>m<ZZ>s or M117 Time Left <XX>h<YY>m<ZZ>s Examples: M118 P0 A1 action:notification Time Left 02h04m06s M117 Time Left 02h04m06s |
print layer progress | M118 P0 A1 action:notification Layer Left <XXXX>/<YYYY> or M117 Layer Left <XXXX>/<YYYY> Examples: M118 P0 A1 action:notification Layer Left 51/940 M117 Layer Left 51/940 |
file data progress | M118 P0 A1 action:notification Data Left <XXXX>/<YYYY> or M117 Data Left <XXXX>/<YYYY> Examples: M118 P0 A1 action:notification Data Left 123/12345 M117 Data Left 123/12345 |
When the trigger print_start
is received, the TFT switches to Printing menu.
When the trigger print_end
or cancel
is received, the TFT Printing menu is finalized (statistics available etc.).
When on Printing menu, pressing on the pause, resume and stop buttons will trigger to the remote host the following notifications, respectively:
NOTIFICATION | ACK MESSAGE |
---|---|
pause | //action:notification remote pause |
resume | //action:notification remote resume |
cancel | //action:notification remote cancel |
The remote host must properly handle the received notifications. For example, if //action:notification remote pause
is received then the remote host must effectively pause the print and send M118 P0 A1 action:pause
in order to trigger the pause action to the TFT.
NOTES:
The TFT can display embedded G-code thumbnails in the file viewer using two different flavors:
The first type is to store the thumbnails at a specific location in the G-code file using a dedicated Cura plugin or external post-processing script. The thumbnail's image data is raw encoded in a format which can be displayed on the TFT without any complex image transformation. Displaying these embedded thumbnails at the TFT is the fastest approach and suitable for all different BigTreeTech's TFT variants. Downside is that you either need a dedicated plugin, for example the BTT 3D Plug-In Suit, or you have to use the post-processing script.
The other type is to store the thumbnails using dedicated comments (thumbnail begin...
and thumbnail end
) which is implemented in stock by some slicers like Prusa-Slicer.
The thumbnail's image data is a PNG file encoded in Base64 which cannot be displayed directly on the TFT:
A base64 decoding and png decoding needs to be performed which is quite complex for the TFT.
Displaying these thumbnails is slower but more flexible.
Due to the memory requirements it is not suitable for all the different TFT variants (only for those with RAM_SIZE > 96
).
Thumbnail generation needs to be specifically enabled in Prusa-Slicer. Under Printer Settings at the G-code thumbnails settings you have to enter the specific required thumbnail image size for your TFT.
Thumbnail image sizes are:
70x70
: TFT24 / TFT2895x80
: TFT43 / TFT5095x95
: TFT35160x140
: TFT70If this setting is not visible within the Prusa-Slicer you need to enable Expert Settings Mode:
The most recent version of the standard bigtreetech TFT firmware has built in support for RepRap firmware. The pre-built images have this enabled by default.
There is now an RRF config file. It needs to be renamed from config_rrf.ini
to config.ini
for updating the configuration of the TFT for RRF.
Add the following line to your config.g
to enable the screen: M575 P1 S2 B57600
.
The following mainboards are covered by this document:
The TFT35 E3 V3.0 has 3 cables to connect to the mainboard. Two 10 pin ribbon cables and one 5 pin serial cable. The 2 ribbon cables connect to the EXP1 and the EXP2 connections on both the TFT35 E3 V3.0 and the MKS mainboards.
The RS232 cable is connected to the RS232 connection on the touchscreen, with the other end connecting to the AUX1 connection on the mainboard. The RS232 cable has 5 wires. One end has a single 5 wire connector that goes to the RS232 connector on the touchscreen, and the other end has two connectors, one has 4 wires, and the second one has one wire. That single wire is for the Reset and is not used on these MKS mainboards. The 4-pin connector plugs into the AUX1 connection. It must connect to the top row of pins when looking at the socket with the notch facing away from the mainboard and must be also plugged in with the 5v+ wire connected to the first pin in the upper left corner of the socket. The RESET wire is not connected to anything.
NOTE: On the MKS mainboards there is an issue that involves at least the MKS GEN_L, MKS SGEN, and MKS SGEN_L models. The EXP1 and EXP2 connections have the socket shell installed wrong way around. The notch that indexes the cable should be facing towards the mainboard. If you get a blank screen on the TFT35 E3 V3.0 touchscreen after connecting the two EXP cables and turning the printer on, turn printer off and disconnect the 10 pin cables from either the touch screen or the mainboard and using small diagonal cutters trim the tab down to be as close to flush as you can get on both cables (and only on one end) and plug them back in with the trimmed tab now facing the mainboard.
The second workaround for this issue is to carefully pry the two shells surrounding the pins on the mainboard upwards until they clear the pins. Do NOT use a metal tool for this, use a sturdy plastic or whalebone prying tool. Turn the shell 180 degrees and align the pins with the holes in the shells and push the shells back on with your thumb. Do not push the shell back on with something that could cause damage if it were to slip. Once the shells are installed you can use the stock (unaltered) cables as they are.
Edit the Configuration.h
file and enable (uncomment) REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
. Rebuild and deploy the Marlin firmware to your 3D Printer.
Statistics as filament length, filament weight and filament cost can be embedded into the G-code. After the print is finished there will be an infobox that you can click and a popup will present you the printed filename (limited to the first 25 characters), the time needed for the print, the filament length used, the filament weight and its cost. In the case of multi-filament usage the statistics will show the sum of all individual data (sum of length, sum of weight, sum of cost). The statistic data in the G-code must have the following format (a good practice would be to include this at the beginning of the G-code):
M118 P0 filament_data L:{12.3456}m
L: represents the length in metersM118 P0 filemant_data W:{1.23456}g
W: represents the weight in gramsM118 P0 filament_data C:{0.1234}
C: represents the cost without a unitThe values of every filament data can be in a brackets, parentheses, apostrophes, etc. or without them, measurement units can be there or not.
So M118 P0 filament_data L:(12.3456)m
, M118 P0 filament_data L:12.3456meters
, M118 P0 filament_data L:[12.3456]
and so on are all valid formats.
For multi-filament print statistics the data for each used filament should be written, they can be separated by comma, space, asterix, whatever, except ;
and .
.
Examples for multi-filament:
M118 P0 filament_data L:(12.3456, 8.2520974)m
M118 P0 filament_data W: 24.87652 15.568264 gramm
M118 P0 filament_data C:[1.3456], [0.56024]
The inclusion of the filament data into the G-code can be automated. In Cura all you have to do is to insert the following into the Start G-Code:
M118 P0 filament_data L:{filament_amount}m
M118 P0 filament_data W:{filament_weight}g
M118 P0 filament_data C:{filament_cost}
In case the G-code file has been generated using the BTT 3D Plug-In Suit, the data is automatically added.
In case filament data is not present in the G-code, the filament length data is calculated during print. Length is calculated regardless of using the TFT USB, TFT SD or the onboard media. Calculations are done in both absolute or relative extrusion mode. Filament data takes into account the flow rate also but with a caveat. It has to be the same flow rate during the entire time of the printing, because the end result is calculated based on the flow rate at the time the print has finished. If flow rate changes during the print the results will not be accurate anymore.