Memory card to IDE adapters aren’t always as plug & play as one would hope. I think trying a few other adapters will be required in this case unless someone else knows better when it comes to that particular PC.

Sounds like your Bios drive geometry is getting translated incorrectly some how to the SD. Writes go in, but the reads that come back out are unexpected. Maybe there are regions where different sectors are mapped to the same spot on the SD.

I would try:
1) Double check the bios settings to make sure the IDE drive geometry makes sense (config works with any bios limitations and the SD size)
2) Install disk overlay software like Ontrack to replace your int13 handler
3) Swap out the IDE controller and cable, becuase maybe somethings flaky eletrically
4) Try an option rom like XTIde or Promise IDE external bios

Or you could buy a CF adapter and a CF for not much money, but if it is a drive geometry problem, not 100% certain this would fix your issue.

Thanks! I used WhatIDE and also tried other drive geometry settings and various drive sizes but no luck. I also tried Ontrack, which looks really cool but it didn't work either.

I'll probably test another adapter and report back if that worked.

I also tried a StarTech CF to IDE adapter but no luck on that either! It has the same issue that it recognizes and writes to the drive but times out while trying to read. I checked the cables so I guess the next thing is to buy an external IDE controller and use up one of the two ISA slots. There must be some incompatibility between the onboard AT-IDE controller and these adapters...

Dzaaneez wrote on 2022-02-27, 23:50:

I also tried a StarTech CF to IDE adapter but no luck on that either! It has the same issue that it recognizes and writes to the drive but times out while trying to read. I checked the cables so I guess the next thing is to buy an external IDE controller and use up one of the two ISA slots. There must be some incompatibility between the onboard AT-IDE controller and these adapters...

Most IDE controllers from that vintage are little more than ISA pass through connectors. Switching to another simple pass through controller isn't likely to do much.

Seems likely it's that your issue is related to the interaction between your BIOS and the IDE side of the Sinitechi adapter.

Maybe you can find a BIOS upgrade for your computer. If you can't find that, consider replacing your int 13 handler by adding an option ROM like the XTide Universal BIOS or installing drive overlay software.

If those don't work, you can look at spending some money on an IDE controller that comes with a proprietary option ROM like the Acculogic, Adaptec, or SIIG models, but those cost top dollar.

Just to make sure: you are connecting a power plug to the adapter as well as the IDE cable, yes?

Okay, thanks - I have the newest BIOS version for this model but I will try the overlay software again and then maybe the universal bios. Should I just get an XT-IDE 8-bit ISA-to-CF card? This computer has 16-bit ISA so would a card like this work?: https://www.ebay.com/itm/185307873110?hash=it … ~QAAOSwByliAMaD (Or is this also just pass-through?)

Yes, both SD and CF adapters are hooked to power - the LEDs are on and they are detected properly by the computer. I can partition, format, and write to the SD card and CF card (and I confirmed this is working by reading the data back on a modern computer). BUT when I try reading data on the Tandy, the activity LED stays lit and then the command eventually times out.

As others mentioned the BIOS seems the more likely culprit, considering you already tried a few different cards and adapters. You don't need the full XT-IDE 8-bit ISA-to-CF card, although it's probably the most convenient option. However if you install a network card with a boot ROM socket you can burn an EPROM with XTIDE Universal BIOS and then you should be able to use either the built-in controller or one like the one you linked to without problems.