Those SD to CF adapters usually require 3.3v power.

If your CF adapter doesn't have a voltage regulator, your SD to CF adapter is unlikely to work.

Some CF to IDE adapters have a jumper and a voltage regulator that allows them to provide 3.3v power.

If you have one of them, try changing it to 3.3v.

So far I haven't had luck SD to CF adapters. I tried have few, type 2, type 1, with full sd and with micro sd slots.

While they work fine in CF card readers, none of them worked in any computer. I've tried amigas, thin clients that have CF slot on motherboard, so no additional adapter required, and regular PCs.

I'll have to try to see if I have any adapter with voltage regulator and try again 🤔.

Huh, my adapter has no voltage...input? it just looks like a compact flash card but with an sd card slot cut into it. Am I missing something here?

geos wrote on 2022-10-24, 08:48:

Huh, my adapter has no voltage...input? it just looks like a compact flash card but with an sd card slot cut into it. Am I missing something here?

Your "SD to CF "adapter requires 3.3V power. That cannot be changed.

You need a "CF to IDE" adapter that can provide 3.3v power and it needs to be set to provide 3.3v power. It would look like this:

If you don't have a jumper that lets you select between 5v and 3.3v power, you need a different "CF to IDE" adapter that can provide 3.3V power

...or you can skip the CF pin out all together and get an "SD to IDE adapter" that has a built in voltage regulator and connects to a HD power (4 pin molex ) connector or a floppy drive power (4 pin berg) connector.

oh

douglar wrote on 2022-10-24, 01:54:

Those SD to CF adapters usually require 3.3v power.
Some CF to IDE adapters have a jumper and a voltage regulator that allows them to provide 3.3v power.

How would that work? There are no separate 3.3V and 5V pins on CF slot. Afaik all CF cards are supposed to operate at 5V. http://www.enide.net/webcms/uploads/file/proj … sh_spec_2.0.pdf
If you stick something that can only accept 3V to 5V slot it will either work but not like it, or will instantly fry.
The only possibility for not working but also not frying to happen would be a product with explicit OVP. Im not liking the voltage theory. Would love to see insides of one of those SD CF adapters.

rasz_pl wrote on 2022-10-24, 21:48:

How would that work? There are no separate 3.3V and 5V pins on CF slot.

My experience with the SD->CF adapters has been that they don't work at 5V but work at 3.3V.

I had just assumed that the reason why is because while CF's devices are supposed to run at both 5V and 3.3V, SD devices require 3.3V.

Here is a CF adapter that supports either 5v or 3.3v power to the CF device.

It has a voltage regulator to step the voltage down from 5v to 3.3v. Not all CF adapters have this.

Internally, my SD-CF adapter has an FC1307a chip with firmware revision Rev 1.3.

If you look at the generic FC1307a SD to IDE adapter, you will see that it has voltage regulator

I imagine that the CF sized packaging doesn't have the thermal capacity to include a voltage regulator.

edited - Had trouble posting the correct pictures

Compact flash cards (include SD to CF adapters) are all meant to be able to operate at either 3.3v or 5v as per compact flash specifications. Some are cheap/non-standard and only work with 3.3v, hence the jumper and voltage regulator.

jmarsh wrote on 2022-10-24, 23:07:

Compact flash cards (include SD to CF adapters) are all meant to be able to operate at either 3.3v or 5v as per compact flash specifications. Some are cheap/non-standard and only work with 3.3v, hence the jumper and voltage regulator.

Specifically in this case, the SD-CF adapter appears to pass the voltage supplied by the CF socket directly to the SD device and SD devices require 3.3V power.

douglar wrote on 2022-10-24, 23:13:

The SD-CF adapter passes the voltage supplied by the CF socket back to the SD device.

SD devices require 3.3V power.

I have a SD-CF adapter. It works fine with 5v power.
The IDE data/address lines also operate at 5v. They are passed directly to the CF socket. Even if the supply voltage is stepped down the same would still need to be done for the data lines, which the CF adapter doesn't handle.

jmarsh wrote on 2022-10-24, 23:17:

I have a SD-CF adapter. It works fine with 5v power.
The IDE data/address lines also operate at 5v. They are passed directly to the CF socket. Even if the supply voltage is stepped down the same would still need to be done for the data lines, which the CF adapter doesn't handle.

Hard to argue with empirical observation. Yours works, mine doesn't.

Mine only worked with v3.3 regardless of which SD I used in the adapter.

Perhaps yours has a voltage regulator in side it or maybe it is some other factor.

Here's my device:

Mine is a type II (fat), so likely.

These converters never worked for me, they just got very hot. 😢

douglar wrote on 2022-10-24, 23:13:

jmarsh wrote on 2022-10-24, 23:07:

Compact flash cards (include SD to CF adapters) are all meant to be able to operate at either 3.3v or 5v as per compact flash specifications. Some are cheap/non-standard and only work with 3.3v, hence the jumper and voltage regulator.

Specifically in this case, the SD-CF adapter appears to pass the voltage supplied by the CF socket directly to the SD device and SD devices require 3.3V power.

that would immediately fry 3.3V device

douglar wrote on 2022-10-24, 23:25:

Hard to argue with empirical observation. Yours works, mine doesn't. […]
Show full quote

jmarsh wrote on 2022-10-24, 23:17:

I have a SD-CF adapter. It works fine with 5v power.
The IDE data/address lines also operate at 5v. They are passed directly to the CF socket. Even if the supply voltage is stepped down the same would still need to be done for the data lines, which the CF adapter doesn't handle.

Hard to argue with empirical observation. Yours works, mine doesn't.

Mine only worked with v3.3 regardless of which SD I used in the adapter.

Perhaps yours has a voltage regulator in side it or maybe it is some other factor.

Here's my device:

Adapter.pngAdapter.png

This is exactly the device that's not working for me.

rasz_pl wrote on 2022-10-24, 21:48:

Would love to see insides of one of those SD CF adapters.

Here ya go.
https://imgur.com/a/6LfT5tS
edit: don't bother asking what the identification on the big chip is, it's been sanded off.

As for the voltage regulation on those cheap CF to IDE adapters...
more often than not they cheap out and use two diodes to drop the voltage,
which is just horrible !

Thank you! Looks like no supply regulator and no OVP circuit.
https://pdf1.alldatasheet.com/datasheet-pdf/v … C2/FC1306T.html
>+5.5V ~ +3.0V wide range power supply.
>14 P VCC5IP Host voltage: 3.3v/5v
>48 P VCC5IP Host voltage: 3.3v/5v
>67 A V33_OUT 3.3V Regulation Output

those are pin numbers for 128pin FC1306, sadly they dont seem to match what I see on your photo of FC1307, but the rest sure does confirm chip is multi voltage tolerant and has own internal 3.3V source.

There is no way for a 3.3V only chip to work ok when plugged into 3V device, and gently refuse to work in 5V without frying. What might be going on here is sly Chinese Muntzing https://en.wikipedia.org/wiki/Muntzing where they removed too many bypass capacitors preventing it from working reliably on unclean 5V rail.