If the drive is recognized by the BIOS, but simply misconfigured in terms of cylinders, heads, etc. you can try adding this on a bootdisk : http://kevparr.com/misc/whatide.php
Helped me find the geometry for a couple of CF and SD cards.

Beegle wrote:

If the drive is recognized by the BIOS, but simply misconfigured in terms of cylinders, heads, etc. you can try adding this on a bootdisk : http://kevparr.com/misc/whatide.php
Helped me find the geometry for a couple of CF and SD cards.

That looks like a cool program, thank you. Unfortunately, I cannot get the motherboard to recognize the IDE-to-CF adapter, so I'm unable to run FDISK.

A wrong geometry should't hurt, though, as long as the max. capacity isn't exceeded.
( It's fake anyway, there are no mechanical parts that can be harmed.. )

Back in the 90s we already did something like that with an old Conner drive (the PC had no type 47)
But yes, I agree it's more elegant to use the CF cards official drive geometry (if available).

Edit: Some 286/386 BIOSes had an HDD auto detection feature. Did you try that, too ?
If it's not working there, you could also try to use the HDD detection feature of a modern PC.
It should be able to report both LBA and CHS values. Maybe even those for ECHS/Large.
Maybe you're lucky and a generic USB card reader is also supported in your BIOS (I doubt it, but you never know).

Yeah, I put mine (512MB) in a different computer and wrote down the numbers.

Asaki wrote:

Yeah, I put mine (512MB) in a different computer and wrote down the numbers.

Same here - a bit of a pain but was the easiest option for me.

This is what I do as well: install the CF to my ss7 pc, write down the geometry that BIOS reports and use these values on the older pc.

Alternatively and to save yourself the trouble you can add this tiny-yet-miraculous utility to a boot disk and query the parameters from the system you intend to use the CF on. Bonus: there were cases were a modern system's BIOS would come up with some weird (LBA to blame I guess?) values for a CF and this little thing turned out to be my Savior and Lord.

Thanks everyone. Never occurred to me to try it with another system, and I have two others that use CF cards! Sometimes the most obvious solution eludes you. The utilities might come in handy if this method doesn't work. Still, I fear that this old system may not work with the adapter I have. I have others on order that I can try once they arrive.

Jo22 wrote:

A wrong geometry should't hurt, though, as long as the max. capacity isn't exceeded.
( It's fake anyway, there are no mechanical parts that can be harmed.. )

Just be aware that if you do this, you won't be able to move the CF card to another PC (or USB card reader) to update it. Plus if your CMOS settings are lost, you need to match the exact settings or you'll lose data. Probably not such a big deal if the card is internal, but if you use one of those adapters that fits into a rear slot so you can swap cards in and out without opening the case, it's more important to get the right values!

For me, the real challenge is finding the right values that will work with standard LBA conversions, so I can put the CF/SD cards into a modern PC, copy all my games and utilities across, then stick them back in the retro PCs and be able to access all the new files. It makes spinning up a new retro PC much quicker!

There was some discussion somewhere about certain CF-IDE adapters not working with certain older IDE cards. Something to do with unused pins being grounded which were later assigned a use, if I remember correctly. I think the solution involved cutting some PCB traces, but I switched to SD-IDE adapters before finding this and I found they were much more reliable so haven't followed up on it, as the SD adapters and SD cards are much cheaper than CF equivalents in my part of the world.

When all else fails, I found that sticking the XTIDE BIOS into a system autodetects the drive and does the correct LBA conversions so this makes machines boot with no manual configuration, even on machines that have IDE support in the BIOS. (I have a 486 that uses the wrong LBA conversion in the BIOS so I can't move storage cards to other PCs, but with the XTIDE BIOS handling things it all works fine.)

boxpressed wrote:

Thanks everyone. Never occurred to me to try it with another system, and I have two others that use CF cards! Sometimes the most obvious solution eludes you. The utilities might come in handy if this method doesn't work. Still, I fear that this old system may not work with the adapter I have. I have others on order that I can try once they arrive.

I've installed a few of those things now and have learnt to order 2x what I need, coz 50% have been dodgy. The most painful experience was with my 286 - the existing oldschool HDD needed to have a a jumper set to allow a slave to work alongside it. It's always worth the effort though; being able to whip the CF card out and copy files onto it is priceless, and being able to back up each system is also a win.