MainBoard Firmware Updates

Latest Version: 1.0.0

Firmware for the mainboard is updated from the SD card. No programmer, no cables. Copy a file, power on, done.

Download: monitor.bin

The file must be named exactly monitor.bin. The bootloader looks for that name and nothing else, and the SD card is read using short (8.3) filenames, so a longer name like MonitorBTL.bin cannot even be opened. The download above already has the right name, but check that your browser did not add (1) or .txt to it.

Update Instructions

Download the firmware

monitor.bin, or build it yourself from the Clura Enclosure repository .

Prepare the SD card

Copy monitor.bin to the root of the card, not inside a folder.

The card must be formatted FAT32. exFAT is not supported, which catches people out with cards larger than 32 GB.

Power off

Remove power from the enclosure.

Insert the SD card

Into the mainboard slot.

Power on

The screen shows the update page, then a success page, and the enclosure reboots itself into the new firmware.

Done

monitor.bin is deleted from the card automatically once the update has been verified, so it will not re-flash on every boot. You can leave the card in.

What happens during an update

The bootloader is careful about the order it does things:

Checks the file size, rejecting anything too small or too large to be firmware
Reads the whole file, proving the card can actually deliver every byte
Checks it looks like firmware, by validating the image header
Only now erases your existing firmware
Programs the new image
Reads it back and verifies what was actually written
Deletes monitor.bin, only after all of the above passed

If any check fails, the enclosure shows the failure page and your existing firmware is left completely untouched. Nothing is erased until the new image has been read and validated, so a corrupt file or a flaky SD card cannot leave you with a dead board.

If the update does not work

Nothing happens at all. The file is not named monitor.bin. This is by far the most common cause. Check for a hidden .bin.txt extension too.

The failure page appears. The image was rejected before anything was erased, so your enclosure is fine. Copy the file to the card again, since the usual cause is an incomplete copy.

A failed update does not delete monitor.bin, on purpose, so a one-off bad read simply retries on the next boot. The downside is that a genuinely corrupt file fails on every boot until you remove it. If you are stuck on the failure page, take the card out and check the file.

The card is not detected. Reformat as FAT32 and insert it before powering on.

The failure page appears with no SD card in. That means there is no valid application in flash to run. Copy a good monitor.bin to a card and update.

Your settings are safe

Your settings, calibration and filament library live in the mainboard’s internal memory rather than on the SD card. A firmware update does not erase them.

Leave data.clu on the card for the first boot after an update. A firmware update can reset the tuning values to their defaults, and if the file is present it re-applies itself straight away. See Configuration.