Compact Flash Cards

  • Thread starter Thread starter Bill
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Bill

Greetings to all -
I'd like to get some recommendations for Compact Flash cards.
In order of importance, they need to address the following:
1. Stability
2. Speed
3. Price

We were using 512MB Sandisk Ultra II's for a quite a while, and they are
hard to find now in comparison to the 1GB's - however we are finding the
1GB's to have a marked performance decrease.

Any information would be sincerely appreciated.
--Bill
 
Bill said:
We were using 512MB Sandisk Ultra II's for a quite a while, and they are
hard to find now in comparison to the 1GB's - however we are finding the
1GB's to have a marked performance decrease.
Click to expand...

We are also using Sandisk Ultra II in 512MB, 1 and 4GB, with good
results. Important for us is good support of DMA mode (actually we had
to modify our card sockets with a wire jumper to enable DMA) and the
tool to set them as fixed disk.

But I can agree that the 512MB looks a bit faster than the 1GB...
Any information would be sincerely appreciated.
--Bill
Click to expand...

Ralph.
 
Bill said:
Greetings to all -
I'd like to get some recommendations for Compact Flash cards.
In order of importance, they need to address the following:
1. Stability
2. Speed
3. Price

We were using 512MB Sandisk Ultra II's for a quite a while, and they are
hard to find now in comparison to the 1GB's - however we are finding the
1GB's to have a marked performance decrease.

Any information would be sincerely appreciated.
--Bill
Click to expand...

We switched from Sandisk Ultra II to Lexar Platinum II's - 80x. The Lexars
were substantially faster, and the price was about the same. We haven't had
stability issues with either brand.
 
Judah said:
We switched from Sandisk Ultra II to Lexar Platinum II's - 80x. The Lexars
were substantially faster, and the price was about the same. We haven't had
stability issues with either brand.
Click to expand...

Is there a tool available switching them into fixed disks? And do they
support DMA?
 
Un bel giorno Ralph A. Schmid, dk5ras digitò:
Is there a tool available switching them into fixed disks? And do they
support DMA?
Click to expand...

Can someone explain to me what is this thing of removable/fixed disks? I've
used a lot of different CF with XPE, not doing anything particular to
switch them as fixed disk, and I've never had a problem.
 
Can someone explain to me what is this thing of removable/fixed disks? I've
used a lot of different CF with XPE, not doing anything particular to
switch them as fixed disk, and I've never had a problem.
Click to expand...

In my opinion there are several problems in using CF in removable mode.
First of all, if you need it, you can't have pagefile. You cannot partition
the drive so you can't setup an OS partition and a "data" partition and
protect only the first one with EWF. Another limitation I found is that the
SMTP server warn you for the fact of setting up log files on a removable
drive.

Ricky
 
Un bel giorno Ricky digitò:
In my opinion there are several problems in using CF in removable mode.
First of all, if you need it, you can't have pagefile.
Click to expand...

Hmmm, creating a pagefile on a CF doesn't sound as a good idea anyway.
You cannot partition
the drive so you can't setup an OS partition and a "data" partition and
protect only the first one with EWF.
Click to expand...

Probably fdisk can't do that (as well as a lot of other things), but I
don't see any technical reason to make it impossible. IIRC the partition
editor of Drivesnapshot can do that, but I should check.
 
Hmmm, creating a pagefile on a CF doesn't sound as a good idea anyway.
Click to expand...

I agree. But I was only speaking on limitations.
Probably fdisk can't do that (as well as a lot of other things), but I
don't see any technical reason to make it impossible. IIRC the partition
editor of Drivesnapshot can do that, but I should check.
Click to expand...

Disk management of XPe can't do this. I don't know if other apps can.

Ricky

P.S. Are you italian?
 
XP and XPe can only see one partition on a removable disk. The problem used
to be when trying to implement EWF to protect the flash life.



Most CF cards don't have wear-leveling technology. XP likes to perform lots
of reads and writes to the drive (erase cycles), which can affect the life
of the flash. To protect the life of the flash you can use EWF or FBWF. Back
when we only had EWF, EWF want to create a second partition for the EWF
volume. Since most CF cards are ID'd as removable, one had to trick EWF into
RAM-REG overlay mode so a second partition is not create. This has been a
known and well discussed problem for a long time.



Now with FP2007 - there is a setting for RAM-REG in EWF and there is FBWF.



Removable is still problematic with preparation since DOS is needed to prep
the disk.

Regards,

Sean Liming
www.sjjmicro.com / www.seanliming.com
XP Embedded Book Author - XP Embedded Advanced, XP Embedded Supplemental
Toolkit
 
Probably fdisk can't do that (as well as a lot of other things), but I
Disk management of XPe can't do this. I don't know if other apps can.
Click to expand...

It is theoretically possible to be able to create multiple partitions on a drive but to do that your app (driver) will have to :
- either replace disk management stack of XP (quite laborous to implement this)
- or create a disk level filter driver to ignore the removable bit of your particular brand card (see Hitachi sample driver
sources on www.xpefiles.com).


It is not an issue to create multiple partitions on a removable drive. You can use disk raw copy software (e.g., ghost or etc). But
then you still won't be able to see more than one partition of the new disk under XP without the changes mentioned above.

Anther noticeable difference in removable media vs fixed is the default disk caching policies. Obviously, removable media access is
optimized for quick removal and etc.
 
Un bel giorno Ricky digitò:
Disk management of XPe can't do this. I don't know if other apps can.
Click to expand...

Ok, now it's clear, thank you. When I'll need to use more than one
partition, I'll remember this and won't waste hours wondering why I can't
see them. :-)
P.S. Are you italian?
Click to expand...

Yes!
 
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