Once upon a time in a not-so-far away forum, here:
someone found himself in a "queer" situation with an external hard disk case that provided two connections, a USB one and a e-SATA one.
This specific enclosure worked fine with the disk it originally came with as that was a "real" 512 bytes/sector disk and both interfaces exposed a 512 bytes/sector device.
But, once the disk was changed to a "new" one that is one of the so called "Advanced Format" kind, something strange happened.
The e-SATA interface exposed a 512 bytes/sector device
The USB interface exposed a 4096 bytes/sector device.
The net result was that the disk was unreadable when connected through the "other" interface.
Provided "solutions" involved one or more of the following:
- buy a new disk
- buy a new enclosure/interface
- give up and buy a new external disk
- buy new PC's and have everything USB3
Being, besides old and grumpy, also cheap, I proposed instead a "workaround" that after quite a bit of experimenting (thanks to the OP Dave-H) seems like being "good enough" to be useful to other (I hope few) people being affected by the same issue, and that (possibly) may become useful when/if similar issues will present themselves.
Basically the disk is divided into two partitions, the first one being a small FAT12 volume that will always be accessible (both when connected through the 512 bytes/sector interface and when connected through the 4096 bytes/sector one) on which a small batch (and a few needed command line executable used by the batch) resides.
The second partition is a (large or main) NTFS one that can be accessed from the one or the other interface but that needs to be "switched" every time the connection is changed to the "other" interface.
All is needed when you connect the disk is to run the switcher.cmd from the first (FAT) small partition and it will "switch" the second (NTFS) main partition to the appropriate byte/sectors settings.
Though the scope of the thingy is quite "narrow", probably the underlying "principles" may be useful in other situations, we will see.
The attached is version 0.99 which more or less means that all the various batches which were at various releases like 0.06 , 0.07 or 0.09 mod3, since they seemed to work, were suddenly - after very little and mostly esthetical changes - promoted to 0.99 which should give the impression of "not really final, yet almost there".
Edited by jaclaz, 18 March 2015 - 07:22 AM.