Impossible Umbrella   
Anyone have any experience with USB to IDE hard disk adapters? I have a 40Mb IDE disk from the early 1990s, which spins up just fine in the adapter; but is never detected by either Linux or MacOS. Is the drive likely faulty? Or could it be that the jumpers aren’t set correctly to work with the adapter? #retrocomputing #ide
Feb 9, 2025 at 9:37pmWeb
Show threadmhjacobsonFeb 9, 2025

@ImpossibleUmbrella Are you possibly hitting this problem?

https://www.klennet.com/notes/2018-04-14-usb-and-sector-size.aspx

USB adapters silently change the sector size

Why does my drive work when connected directly to a SATA port, but does not work with a USB adapter?

Show threadmbbrutmanFeb 9, 2025

@ImpossibleUmbrella A lot of USB adapters expect the drive to use LBA addressing mode.

An early 40MB IDE drive is probably (make that almost absolutely) only going to use CHS mode for addressing the sectors. The only way to work with that drive will be to put it on a real IDE controller, not a USB to IDE bridge.

Show threadImpossible Umbrella   Feb 9, 2025
@mbbrutman Ah. I didn’t know about this. Thanks.
Show threadmbbrutmanFeb 10, 2025

@ImpossibleUmbrella Another thing to be aware of is that even on modern drives, a lot of these adapters don't have power supplies that are adequate for spinning an IDE or a SATA drive. Even the ones that supply external power and are not just powered off of the USB port.

I've run into that problem regularly. My newer USB 3.0 adapter with external power won't spin up a SATA drive, but my older USB 2.0 "dock style" adapter will. It's irritating. I have a variety so that I can get one working.

Show threadImpossible Umbrella   Feb 10, 2025
@mbbrutman Yes, now that one I did think about it- and was sure to get a dock style one with a 12V supply (and the disk spins up and does something I presume is loading thr heads) no problem.