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Hey David,

A micro SD card with a working copy of Raspberry Pi OS has two partitions on the card:

?? - Partition 1 - FAT32 file system - holds /boot : A windows or Mac computer can read / write these files

?? - Partition 2 - EXT4 file system - holds all other parts of the OS, home directories, etc.: A Windows or Mac computer will NOT be able to see this file system or read/write any of these files



You can see these partitions using the Linux command (here is an example for a Samsung 16GB micro-SD card):

?? sudo fdisk -l /dev/mmcblk0
?? --
?? Disk /dev/mmcblk0: 14.9 GiB, 15931539456 bytes, 31116288 sectors
?? Units: sectors of 1 * 512 = 512 bytes
?? Sector size (logical/physical): 512 bytes / 512 bytes
?? I/O size (minimum/optimal): 512 bytes / 512 bytes
?? Disklabel type: dos
?? Disk identifier: 0x92f034a6

?? Device???????? Boot Start????? End? Sectors? Size Id Type
?? /dev/mmcblk0p1?????? 8192??? 93813??? 85622 41.8M? c W95 FAT32 (LBA)
?? /dev/mmcblk0p2????? 94208 31116287 31022080 14.8G 83 Linux
?? --


I think the issue that you're seeing here is an issue with your SD card *reader* on your other PC.? What *capacity* is your MicroSD card?? Is it larger than 32GB?? What is the labeling on your SD card reader? ? Does it have writing on the card showing compatibility for:

?? - SD
?? - SDHC
?? - SDXC
?? - MMC

If I was to guess, you have a 64GB card and you're reader either doesn't have or has incomplete SDHC support.? I have been bitten by older SD card readers mis-reading bigger SD cards and if they seemed to read ok, writing to them would corrupt the SD card's file system.? It's really unacceptable that this is possible but I can personally tell you it *IS* possible and has happened to me a few times before.? If this is your scenario, I would recommend to *recycle* that old SD card reader and get something newer that has proper SD card support to avoid trashing future card events.

--David
KI6ZHD

After successfully using my Rpi 4 B+ for a few months as part of my homebrew mobile manpack rig I decided to back up the SD card prior to installing a GPS dongle. I did a sudo shutdown -h now and powered down. When I stuck the SD card it into my PC it was blank, save for the volume label.?

After failed attempts to recover the data, I flashed a new card, installed Hampi again, started reconfiguring Flrig etc., Then I decided to double-check the new card. I did the graceful shutdown before pulling the card out but evidently wiped that one as well at some point in the process. All files were gone but for a couple of text files and the volume label.

Subsequent online research indicates maybe I didn't let the pi shut down all the way before pulling the card. I did not know to wait for flashing lights after shutting down. However, I'm pretty sure I powered it down all the way after several seconds.?After spending hours flashing cards and looking forward to the prospect of going back to square one yet again and then reconfiguring the software again, and hoping it doesn't happen a third time, I am thinking the pi may just be too fragile a system to rely upon for emergency/mobile comms. It seems crazy that the SD card should be so vulnerable to erasure simply by being extracted from the Pi.?

At this point I am planning on just using the Toughbook that I was using as a keyboard/screen interface to host the software and cut out the Pi. It's a shame since I've invested countless hours in getting Hampi up and running.

Has anyone else had this experience?

David AJ6RE??

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