Problem: SD card section in blackbox menu states: Fatal error Reboot to retry
fc: Matek F722-SE
Bf: Betaflight 4.0.4
rx: Frsky R-XSR
tx: Frsky x-lite
vtx: RDQ Mach 1
vrx: FatShark Scout
Solution: Your SD card needs a valid FAT32 partition in order for Betaflight to recognize it and use it for black box.
To see if this is your problem:
- Betaflight CLI
- If the card is detected by Betaflight (shows manufacturer, size, etc) but error message is ‘no FAT MBR partitions‘ – it is because you need a FAT32 partition on your card
- exFAT and NTFS volumes cannot b read by flight controllers in Betaflight (at this time)
Default Windows behaviour does not allow you to create a FAT32 volume larger than 4 GB. There are two sets of instructions. One is if you have a card 4GB or smaller and can use Windows disk utilities and the other is a small 3rd party tool that can quickly format a much larger FAT32 partition for you.
First make sure there is nothing valuable on the card!
- Remove SD card from flight controller and mount it to your Windows PC (via USB, or SD slot if you have it)
- Run -> diskmgr
- Select your SD card from list of disks in Windows
- Right click any existing volumes
- Delete volumes until there are no volumes on the SD card
If you have a 4GB card or lower:
- Right click unallocated space
- Create a ‘New Simple Volume’
- Use 4096MB as the volume size
- Select file system as FAT32 using drop down
- If FAT32 is not an option, go back and make sure that your volume size is not over 4096 MB!
If you have a greater than 4GB card:
- Put SD card into flight controller
- Open Betaflight
- Filesystem: Ready indicates things are fine or Filesystem: Initialize and returning to Ready after
- If Filesystem: Initialize is taking a long time
- Betaflight CLI – sd_card dma = off
- Change Blackbox logging rate down to 4 kHz or less
- These two changes worked for me
With all of this, you should be ready to go ! Hopefully larger volumes will be able to be used in the future, but this is quite common with these type of boards – ie a Raspberry pi expects to be booted off of a FAT32 volume.