Need input on CF to IDE adapter hack

myersn024 · Post by **myersn024** » Wed Jan 16, 2008 11:29 pm

I know that there are adapters out there that allow you to use a CF card in place of an IDE harddrive. What I'm thinking about is making an adapter that allows you to go the opposite direction. According to the info that I found on pinouts.ru, the CF to IDE adapter is a simple translation of the pinouts...no microcontrollers at all. Does that mean that the same adapter could be used to allow a device equipped for compact flash to access an IDE drive?

Post by **gannon** » Thu Jan 17, 2008 10:51 am

Only if they access the CF card in IDE mode. Also, you have to be aware of potential size limitations (like some devices only work with storage <= 2GB)

myersn024 · Post by **myersn024** » Thu Jan 17, 2008 10:53 am

I was already aware of the size limitations, but I didn't know that there was more than one way to access a compact flash device. I thought they were originally designed to act as small solid state IDE disks.

*EDIT*
I just did a little more searching, and everything I've found says that there is no electrical difference between the IDE interface and the CF interface. IDE drives and CF cards were being developed at roughly the same time, and their built on the same standards.

I think I'm going to go by Wal-Mart and pick up a cheap USB compact flash reader. Then I'll take it apart and try to wire an IDE hard drive up to it. If my theory is correct, I should be able to access the IDE drive through the CF reader.

If anyone has any advice or tips on how to do this, I'm all ears.

nitro2k01 · Post by **nitro2k01** » Thu Jan 17, 2008 12:28 pm

I've had the same idea. My theory on the other hand is that CF uses only a subset of the IDE protocol. So in other words the CF controller might not be able to detect a CD-ROM or HD because it doesn't know to communicate with it.

myersn024 · Post by **myersn024** » Thu Jan 17, 2008 12:41 pm

That may be true, but here's what wikipedia says

CompactFlash defines a physical interface which is smaller than, but electrically identical to, the ATA interface. That is, it appears to the host device as if it were a hard disk of some defined size and has a tiny IDE controller on-board the CF device itself.

I take that to mean that the compact flash reader doesn't have to control anything. The hardware part of the controller is built in.

timmeh87 · Post by **timmeh87** » Thu Jan 17, 2008 12:48 pm

The biggest problem I see is powering a hard drive from something thats designed to take CF cards

myersn024 · Post by **myersn024** » Thu Jan 17, 2008 2:21 pm

Yeah, it'll require another battery or some kind of external power supply.

tom61 · Post by **tom61** » Thu Jan 17, 2008 2:35 pm

What device are you going to plug it into? Whether or not it will work will depend on the device. As gannon said, there are two different interface modes: PCMCIA and IDE. Nearly all PDAs use PCMCIA mode. Most single board computers, many homebrew devices and certian adapters use IDE.

There was a link posted somewhere on these boards to a person that rigged up an IDE harddisk to an adapter that let you plug CF drives to a Nintendo DS.

myersn024 · Post by **myersn024** » Thu Jan 17, 2008 2:57 pm

I found this -> http://www.natrium42.com/blog/?p=39 which has to do with connecting a laptop harddrive to an NDS for use with GBAMP. No where in his post did he mention more than one type of protocol, and what I'm trying to do is actually pretty similar to what he's done. I'm wanting to take something like this -> http://www.ic2005.com/shop/product.php? ... t=9&page=1, and convert it to be able to use a hard drive. If I can pull it off, I shoud be the first one to do it with a PSP.