There is a marvelous tool simply called testdisk
https://www.cgsecurity.org/wiki/TestDisk_Download (https://www.cgsecurity.org/wiki/TestDisk_Download)
Cards are not damaged. They are used in microcontroller operated devices and probably has some custom memory organization.
I hoped I could read them from Windows when some of this devices stop working.
I will try with Linux and if that doesn't work I'll try it with Arduino.
How could SD card be read if there isn't drive letter assigned to it and it doesn't show in Disk Management?
How could SD card be read if there isn't drive letter assigned to it and it doesn't show in Disk Management?
I've been told that an SD card appears as a file on Linux, macOS and Windows. But, I have no clue what this is or how to access it.
I have the same query as you, about accessing an SD card that the OS doesn't recognise the format but is not broken.
This is the second or third time I've said this in this thread: look at it using something like an Arduino since you're likely to need to get at it at a lower level than off-the-shelf PC interfaces support. Or at the very least use an RPi rather than a PC, but at that point expect to have to port Arduino code onto it since that's where all the work is being done.Unfortunately, people have requested a feature on my application that allows them to access the files on this filing system (which isn't recognised by Windows or macOS, but apparently there is a driver built into Linux...interestingly). The partition they want to access is a RISC OS partition. Majority of the time, this SD card would have come from a RaspberryPi, but sometimes a RiscPC (or older).
This is the second or third time I've said this in this thread: look at it using something like an Arduino since you're likely to need to get at it at a lower level than off-the-shelf PC interfaces support. Or at the very least use an RPi rather than a PC, but at that point expect to have to port Arduino code onto it since that's where all the work is being done.Unfortunately, people have requested a feature on my application that allows them to access the files on this filing system (which isn't recognised by Windows or macOS, but apparently there is a driver built into Linux...interestingly). The partition they want to access is a RISC OS partition. Majority of the time, this SD card would have come from a RaspberryPi, but sometimes a RiscPC (or older).
Even if the SD card has an unsupported file system or even partition table it will still display as a drive in Window's disk manager (cause you might want to reformat it after all). If it doesn't then something is problematic with either the SD card or the reader.This is the second or third time I've said this in this thread: look at it using something like an Arduino since you're likely to need to get at it at a lower level than off-the-shelf PC interfaces support. Or at the very least use an RPi rather than a PC, but at that point expect to have to port Arduino code onto it since that's where all the work is being done.Unfortunately, people have requested a feature on my application that allows them to access the files on this filing system (which isn't recognised by Windows or macOS, but apparently there is a driver built into Linux...interestingly). The partition they want to access is a RISC OS partition. Majority of the time, this SD card would have come from a RaspberryPi, but sometimes a RiscPC (or older).
Even if the SD card has an unsupported file system or even partition table it will still display as a drive in Window's disk manager (cause you might want to reformat it after all). If it doesn't then something is problematic with either the SD card or the reader.This is the second or third time I've said this in this thread: look at it using something like an Arduino since you're likely to need to get at it at a lower level than off-the-shelf PC interfaces support. Or at the very least use an RPi rather than a PC, but at that point expect to have to port Arduino code onto it since that's where all the work is being done.Unfortunately, people have requested a feature on my application that allows them to access the files on this filing system (which isn't recognised by Windows or macOS, but apparently there is a driver built into Linux...interestingly). The partition they want to access is a RISC OS partition. Majority of the time, this SD card would have come from a RaspberryPi, but sometimes a RiscPC (or older).
Even if the SD card has an unsupported file system or even partition table it will still display as a drive in Window's disk manager (cause you might want to reformat it after all). If it doesn't then something is problematic with either the SD card or the reader.This is the second or third time I've said this in this thread: look at it using something like an Arduino since you're likely to need to get at it at a lower level than off-the-shelf PC interfaces support. Or at the very least use an RPi rather than a PC, but at that point expect to have to port Arduino code onto it since that's where all the work is being done.Unfortunately, people have requested a feature on my application that allows them to access the files on this filing system (which isn't recognised by Windows or macOS, but apparently there is a driver built into Linux...interestingly). The partition they want to access is a RISC OS partition. Majority of the time, this SD card would have come from a RaspberryPi, but sometimes a RiscPC (or older).
No. I have these devices which initialize SD card and after that cards aren't recognized in Windows or Linux at all. Cards work just fine in the device (device writes data to it and it can read data from card).
I believe dseligo has an SD card that lacks a standard FAT table. it takes 3x the writes to the SD card to properly support FAT32/FAT16 so for both speed and power reasons a lot of firmware just uses something else.
I have seen utilities On both Windoes paid software (winhex?) and Unix free utility (??) that can access the card on a block level, bypassing the OS file manager and the need for a good FAT table on the card.
Can anyone provide better help with this info?
No. I have these devices which initialize SD card and after that cards aren't recognized in Windows or Linux at all. Cards work just fine in the device (device writes data to it and it can read data from card).
Perhaps after initializing the SD card is stuck in SPI mode and can't be brought back into SD mode (though judging from the SD card spec the card should allow this with each power up sequence).
...
Again, it does not matter if the SD card is formatted with FAT or not. If the whole disk is not available in disk management then something else went wrong.
Does the /device/ appear as e.g. /dev/sdb when plugged in? Note that I'm not talking about the /filesystem/ here, or about individual /files/ on the filesystem.
No. I have these devices which initialize SD card and after that cards aren't recognized in Windows or Linux at all. Cards work just fine in the device (device writes data to it and it can read data from card).
What do you mean? Do you mean that it isn't auto-mounted, or do you mean that it doesn't appear as e.g. /dev/sdb?
If it doesn't appear as /dev/sdb then what does the kernel log tell you?
In any case, what sort of device are you using between the card and the PC?
MarkMLl
Noting https://www.riscosopen.org/forum/forums/11/topics/2244 I think the most likely thing is that RISCOS has wiped the partition and initialised a single (SDFS?) filesystem, in which case there's a real possibility that either an external (USB-connected?) interface box refuses to recognise it ** or that the OS (or more specifically, a desktop environment) won't attempt to auto-mount it without manual intervention. In any event, if OP isn't going to tell us what he's doing then he's the one that's stuck.
** That might sound improbable, but SD-Cards are now a subsystem in their own right with their own engineering tradition: e.g. preferred partitioning and filesystem layout to put the FAT onto more-robust storage than is used for the data area. Taking that sort of thing into account, even though I've not seen an interface box present a card as other than a linear sector image (at least to the standard storage APIs, it's entirely reasonable that something of comparatively recent manufacture could get confused if its attempt at clever device management were stymied by a non-standard layout (i.e. no partition table etc.).
Only if I had more time...
As dseligo wrote they can't access it using PhysicalDriveXXX on Windows which means that Windows (and the connected card reader) weren't able to initialize the SD card correctly. If it's only partitioned differently it won't matter, cause as long as the SD card can be initialized correctly it can be accessed (minus bad sectors obviously).
Do you by any chance know how these SD cards were initialized and in what environment they're used? Maybe some of use could try to reproduce this then.
As dseligo wrote they can't access it using PhysicalDriveXXX on Windows which means that Windows (and the connected card reader) weren't able to initialize the SD card correctly. If it's only partitioned differently it won't matter, cause as long as the SD card can be initialized correctly it can be accessed (minus bad sectors obviously).
Yes, /provided/ that the reader device doesn't crash because irrespective of the interface it exposes over USB it gets confused by a (partition table or) filesystem type it's not expecting.
QuoteDo you by any chance know how these SD cards were initialized and in what environment they're used? Maybe some of use could try to reproduce this then.
I think he's already said that they were ordinary cards which became unmountable (to a PC) after an embedded system had put RISCOS on them.