Sunlu T3 Firmware Update [exclusive] -

This report outlines the procedures, benefits, and risks associated with updating the firmware on the (Terminator) 3D printer. The Sunlu T3 is equipped with a 32-bit motherboard, typically a modified version of the BigTreeTech SKR Mini E3 V2 Update Overview Updating firmware on the Sunlu T3 can improve performance, fix factory bugs, and unlock features like increased hotend temperatures or optimized bed leveling. Official Version v3.40 (released Oct 2022) Firmware Type Marlin 2.0 Primary Method microSD Card (Auto-update on boot) Key Hardware STM32F103 MCU (32-bit) Preparation & Requirements Before beginning, ensure you have the following: MicroSD Card: Must be formatted to with a small allocation size (e.g., 4096 bytes). Firmware File: file named exactly firmware.bin for official/custom Marlin, or specifically configured for Official Downloads: Available via the Sunlu Support Page (v3.40 is the latest stable official release). Update Procedure (SD Card Method) Obtain the correct file for your specific machine version. Ensure the microSD card is clean and formatted to FAT32. Copy the file to the root of the SD card and rename it to firmware.bin Turn off the printer. Insert the SD card into the printer's slot. Turn on the printer. The screen may remain blank for 10–30 seconds while the update installs. Once the UI loads, check the "About Printer" or "Info" menu to confirm the new version number. Critical Considerations & Known Issues klipper/config/printer-sunlu-t3-2022.cfg at master - GitHub

Here’s a concise review of the Sunlu T3 firmware update process based on common user experiences and technical notes. Overall Verdict: ⭐⭐⭐ (3/5) – Necessary but clunky Updating the firmware on the Sunlu T3 (a budget Ender-3 clone) can improve print stability and fix bugs, but the process is less user-friendly than mainstream printers like Prusa or Bambu Lab.

What’s Good ✅

Fixes thermal runaway bugs – Early T3 units had false thermal runaway triggers; updates resolve this. Improves mesh bed leveling – Some versions better store and recall ABL data. Silences stepper motors – Later firmwares enable better stealthChop settings for quieter operation. Adds features – Like manual filament change, baby-stepping, and power-loss recovery (though the last is controversial). Sunlu T3 Firmware Update

What’s Bad ❌

No official GUI updater – You must flash via SD card and rename .bin files manually. No USB/Cura direct update. Screen mismatch risk – The T3 uses a third-party touch screen (DGUS or stock Creality-style). Flashing the wrong screen firmware can brick the display. Lack of clear changelogs – Sunlu rarely posts detailed version history. You rely on community forums. Potential feature loss – Some updates disable power-loss recovery to free memory, or break filament runout sensing.

Step-by-Step Experience (Typical User Report) This report outlines the procedures, benefits, and risks

Download firmware from Sunlu’s website or Google Drive link (sketchy, often outdated). Format SD card to FAT32, 4096 bytes. Copy firmware.bin . Insert into printer, power cycle. Wait 30 seconds. Screen stays blue briefly. If successful, file renames to firmware.CUR . If not, nothing changes. For touch screen firmware: Remove screen cover, insert microSD into screen PCB. Harder.

Common Issues ⚠️

Boot loop after update – solved by reflashing stock firmware. Touch screen remains blank – update screen firmware separately (often forgotten). Lost EEPROM settings – PID, e-steps, Z-offset reset. Must recalibrate. Firmware File: file named exactly firmware

Final Recommendation Update only if you have a specific problem (thermal runaway, ABL not saving). Otherwise, keep the stock firmware. If you want better features, skip official updates and go straight to Marlin custom builds (e.g., from Insanity Automation or TH3D) – they’re more reliable and add advanced options like linear advance. Rating: 2.5/5 – It works, but Sunlu’s poor documentation and two-step (mainboard + screen) process make it frustrating for beginners.

To update the firmware on your , you will primarily use an SD card to flash a file directly to the printer's 32-bit motherboard. 1. Prepare Your Hardware uses a 32-bit ARM-based controller board (similar to a BTT SKR Mini E3 V2) . To perform the update, you need: Micro SD card (ideally 8GB or smaller). A computer to format the card and download files. 2. Download the Firmware File You can obtain the necessary firmware from official or trusted community sources: Official Firmware : Historically available on the Sunlu Website (Version 3.40 is a common stable release). Official Archive : A copy of the official firmware is archived on GitHub by denizkoekden Custom Marlin : For advanced features like better fan control or refined Z-offset menus, community-optimized versions are available on Printables by Kaot93 3. Format the SD Card The printer requires a specific format to recognize the update file: Insert the SD card into your computer. Format it as 4096 allocation unit size Ensure the card is empty before proceeding. 4. Flash the Printer Rename the File : Ensure the downloaded firmware is named exactly firmware.bin . If the file has a long string of numbers or dates, the printer may not recognize it. Copy to SD : Move the firmware.bin file to the root directory of the SD card (not inside any folders). : Turn off your Insert Card : Insert the Micro SD card into the printer’s card slot. : Turn the printer on. The screen will remain blank for about 15–30 seconds while it flashes the new code. : Once the main menu appears, go to About Printer to verify the new version number. Printables.com Important Post-Update Steps Reset EEPROM : It is highly recommended to go to Configuration > Restore Defaults Store Settings immediately after updating to ensure old settings don't conflict with new firmware. : Re-calibrate your Z-offset and level the bed, as these settings are often cleared during a flash. custom Marlin profile for the Sunlu T3 to enable specific features like Linear Advance denizkoekden/SUNLU-T3 - Marlin 3D Printer Firmware - GitHub