Firmware 3.7.1-FINAL for Original Prusa i3 MMU2S & MMU2  

Firmware 3.7.1-FINAL for Original Prusa i3 MMU2S & MMU2

WARNING: Note that MK3S, MK3, MK2.5S and MK2.5 are different printers! Each has its own firmware file!!!

Hi guys,
this is a testing version of the firmware recommended to experienced users only 😎

What is new?

• Rambo board overheating fix
• Enabled watchdog for MK2.5S & MK2.5
• Octoprint MMU load failed fix
• Bed preheat error fix
• SPI flash error is not blocking the printer anymore
• IR-sensor self-test fail message added
• Menu items text overflowing fix
• Linearity correction not saved to EEPROM fix

Watchdog fix
In the firmware version 3.7.1-FINAL we added on MK2.5 and MK2.5S printers a watchdog for better safety. In firmware 3.7.1-RC1 the watchdog was only added to MK2.5.

Rambo board overheating fix:
In the firmware version 3.5.2 and higher, we have increased the PWM frequency to reduce noise from the new PSU (black case). In some cases, the Rambo board overheated. We have now reduced this frequency to 32 Hz so that both, old PSU (silver case) and new PSU (black case) are quiet enough and not overheating.

Octoprint MMU load failed fix:
On the older firmware version for MK2.5S and MK3S printers printer doesn't pause after MMU2 load error when printing from Octoprint. The new behaviour is, that when printing from Octoprint T-command failure block execution of following commands. The printer doesn't respond "OK" to Octoprint until T-command is successfully finished. There is blocking message "MMU load failed" on the status screen and each time printer knob is pushed, printer retries filament load to nozzle move.#1652

Bed preheat error fix:
This release fixes false detection of bed preheat error. Minimum temperature rise slope criterion in the time domain was relaxed.

SPI flash error is not blocking the printer anymore:
MK3S & MK3 error message "External SPI flash W25X20CL is not responding." is no more completely blocking printer operation. Now it is shown during splash screen and it is possible to use printer, only available language is English.

Other:
- Enabled watchdog for MK2.5S & MK2.5
- Translation corrections
- IR-sensor self-test fail message added
- Menu items text overflowing fix
- Linearity correction not saved to EEPROM fix

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Supported printers:
Original Prusa i3 MK3S MMU2S
Original Prusa i3 MK3S
Original Prusa i3 MK3 MMU2
Original Prusa i3 MK3

Original Prusa i3 MK2.5S MMU2S
Original Prusa i3 MK2.5S
Original Prusa i3 MK2.5 MMU2
Original Prusa i3 MK2.5

Download link:
prusa3d.com/drivers

Firmware flashing guide:
manual.prusa3d.com/Guide/Upgrading+the+firmware/66

Please report any bug here:
github.com/prusa3d/Prusa-Firmware/issues

As always, we wish you happy printing and look forward to your feedback!