Some CompactFlash doesn't work in True-IDE mode

Hi folks,

Today I found something interesting you might like to know. Some CompactFlash, even with the CF logo, doesn't appear to support True-IDE mode. The specific flash that we had was a Memorex branded flash that, when plugged into an IDE port, comes up in BIOS with a "32M CHH" name.

The funny part is that it forces itself to be the slave device. Here I am with a Geode board with an integrated CompactFlash socket on the secondary master IDE and nowhere to plug anything else in, and the flash comes up as the the slave drive. If you put it into the "normal IDE" to compactflash adapter board and try to run it as master, the thing isn't even recognized.

This was fun to find, as it was simultaneous with a new flash creation tool that uses the Win32 SYSLINUX to create bootable Linux CompactFlash with a minimum of work from a Windows box. When it didn't work, the initial finger was pointed at SYSLINUX. When I pulled all the flash and checked them all, I soon realized that the only flash having problems were those that came up with a "32M CHH" tag, and they all had a 021 mfg code on the side.

These CompactFlash do say "Copyright 2000" on them so I suspect that they were manufactured more than a few years ago. They do, however, have the CF Association logo on them. None of the other Memorex-branded flash I've got has this problem, so I hope that its just some leftover crap from the early days.

Anyway, cheers. I hope someone else someday finds this useful to know.

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Alex Pavloff - remove BLAH to email
Software Engineer, ESA Technology
Reply to
Alex Pavloff
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Though devices sporting the CF logo must support True-IDE mode,they need only implement the subset of commands in the CF 2.0 spec - are you sure your driver isn't using others? Also,they may implement some or all of the commands as no-ops, Sprow.

Reply to
Sprow

It seems to me that at the bare minimum, the CF shouldn't force itself to be the slave device in TrueIDE mode. I don't have the CF spec in front of me, but this seems like it would be a required function.

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Alex Pavloff - remove BLAH to email
Software Engineer, ESA Technology
Reply to
Alex Pavloff

Reply to
Marc Guardiani

[snip]

Alex

I had a similar issue wiht Memorex CF boards. After connecting -DASP and -PDIAG to VCC things started to work.

Maybe this helps you too.

Markus

Reply to
Markus Zingg

I didn't design the board or the socket these things are going into. They're going into a stock Acrosser AR-B1551 board, a 3.5" Geode "biscuit" board (of which there are numerous variations by other companies).

Some more testing results in a bunch of Kingston branded flash of many many different sizes and actual chip mfgs all working just fine, and a stack of 5 021-coded "32MB CHH" flash not.

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Alex Pavloff - remove BLAH to email
Software Engineer, ESA Technology
Reply to
Alex Pavloff

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