16mb buffer hard drive in a laptop

[Al Dykes]

What if we disable the swap file? I wonder if anyone has actually
tried running Windows on a flash disk, or if everyone has just been
scared off by the write-cycle limitation. I have an extra 256MB flash
card, maybe I will try running Win98 off it. A CF to IDE adapter
goes for less about $20.

WinXP embedded can run from flash disk:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/xpehelp/html
/xetbsCompactFlash.asp

H**l; Winxp/embedded can run in a cell phone! (I think that's what
Motorola uses)

I know the poeple that write Pebble, a linux tailored to run from a 64
or 128MB CF card on a small mobo that has 64mb RAM. That's all there
is. I've built a couple systems from the setup scripts.The Pebble
package is a WiFI AP and web server that's widely used for the Free
WiFi zones and local coffe shops. Neat stuff.

www.nycwireless.com/pebble

When Pebble Linux boots it makes some of RAM a memory-resident file
system for run-time data. It runs the binaries of the CF card, but
this file system is marked RO after booting is complete to protect the
life of the CF card. It required some magic to make the Linux kernel
happy running from a RO file system.

There are MAKERW and MAKERO commands so that I can edit configuration
files while the system is running and then make the system disk RO
afterwords.

Pebble is designed to run for years in remote locations. A couple
years ago the guys were conservative about CF card write cycle
lifetimes. I haven't heard that they have changed their mind(s).

 

[J. Clarke]

H**l; Winxp/embedded can run in a cell phone! (I think that's what
Motorola uses)

First, XP Embedded is not quite the same as XP Pro or XP Home. Yes, it can
run from a flash disk, or a CD or a ROM for that matter--it purpose to
existence in fact is that it can be burned into ROM--but it doesn't give
the same functionality. And it's not something that the "average consumer"
is going to have or want.

Second, the cell phones do not run any flavor of XP, they run a variant the
operating system that Microsoft developed to compete with PalmOS, which has
gone through so many name changes that I've given up trying to keep track
of what they call it this week.

I know the poeple that write Pebble, a linux tailored to run from a 64
or 128MB CF card on a small mobo that has 64mb RAM. That's all there
is. I've built a couple systems from the setup scripts.The Pebble
package is a WiFI AP and web server that's widely used for the Free
WiFi zones and local coffe shops. Neat stuff.

www.nycwireless.com/pebble

When Pebble Linux boots it makes some of RAM a memory-resident file
system for run-time data. It runs the binaries of the CF card, but
this file system is marked RO after booting is complete to protect the
life of the CF card. It required some magic to make the Linux kernel
happy running from a RO file system.

There are MAKERW and MAKERO commands so that I can edit configuration
files while the system is running and then make the system disk RO
afterwords.

Pebble is designed to run for years in remote locations. A couple
years ago the guys were conservative about CF card write cycle
lifetimes. I haven't heard that they have changed their mind(s).

You can run MS-DOS from a ROM too.

It is certainly possible to make a machine that uses a flash disk--Palm and
Compaq and many others make such machines and you can buy them at any
office supply store. That has never been the issue. The issue was the
utility of a $40 IDE flash disk as a replacement for the magnetic disk in a
notebook computer used by an "average" consumer.

 

[Folkert Rienstra]

What if we disable the swap file? I wonder if anyone has actually
tried running Windows on a flash disk, or if everyone has just been
scared off by the write-cycle limitation. I have an extra 256MB flash
card, maybe I will try running Win98 off it.

A CF to IDE adapter goes for less about $20.

Is that a CF to CF-IDE adapter -that merely adds the CompactFlash
IDE commandset- that you stick between a CF-card and a CF- slot or
a CF to 40 pin IDE connector adapter?

Is there any difference in running a flashcard like that and just
running a ramdisk on a Flashcard? Aren't there drivers that allow
you to run a FlashCard as a disk (emulating the command set)?

 

[David Chien]

I was looking on froogle and these drives in stores go for upwards of

He claims they're surplus to a project. Might have "fallen off a truck".

works fine for me here. good seller, no problems with the drive.

 

[Shailesh Humbad]

Is that a CF to CF-IDE adapter -that merely adds the CompactFlash
IDE commandset- that you stick between a CF-card and a CF- slot or
a CF to 40 pin IDE connector adapter?

Is there any difference in running a flashcard like that and just
running a ramdisk on a Flashcard? Aren't there drivers that allow
you to run a FlashCard as a disk (emulating the command set)?

AFAIK, you plug the compact flash card into the adapter, and then the
adapter into an empty IDE port. I believe the adapter has minimal
on-board logic, and is basically just a pass-through. After it's
plugged in, it appears to the system just like any other regular hard
disk drive. You have to format and partition it, and then the system
assigns it a drive letter. No drivers are needed.

http://www.acscontrol.com/Index_ACS.asp?Page=/Pages/Products/CompactFlash/IDE_To_CF_Adapter.htm

 

[Folkert Rienstra]

AFAIK, you plug the compact flash card into the adapter, and then the
adapter into an empty IDE port. I believe the adapter has minimal
on-board logic, and is basically just a pass-through. After it's
plugged in, it appears to the system just like any other regular hard
disk drive. You have to format and partition it, and then the system
assigns it a drive letter.

No drivers are needed.

Which means that there must be some logic that imitates a real IDE bus
(which apparently is not all that different from CF in the first place)
and IDE command set and registers.

 

[J. Clarke]

Nonsense. Flash hard drives are designed for harsh environments, and have
ECC and sector remapping just like hard drives.

So what? Any flash chip will have in its datasheet the allowable number of
rewrites. If you're using it in an environment in which writes are
frequent (for example Windows with its page file) then you will use up the
allowable writes in a remarkably short time.

They can use other tricks
like rotating frequently written sectors.

Which delay the inevitable.

Flash memory cards have no smarts, yet I don't see them dropping like
flies.

Flash memory cards are not normally used as primary storage.

 

[Eric Gisin]

So what? Any flash chip will have in its datasheet the allowable number of
rewrites. If you're using it in an environment in which writes are
frequent (for example Windows with its page file) then you will use up the
allowable writes in a remarkably short time.

Then you detect the error and remap the bad sector. Sound familiar?

Which delay the inevitable.

Nope. You have millions of sectors, some of them spares.

Flash memory cards are not normally used as primary storage.

They all have frequently written areas, the FAT and root dir. Why aren't they
dying?

 

[John Turco]

Then you detect the error and remap the bad sector. Sound familiar?

Nope. You have millions of sectors, some of them spares.

They all have frequently written areas, the FAT and root dir. Why aren't they
dying?

Hello, Eric:

"Flash memory cards" will wear out, physically, after a comparatively
brief number of write cycles (100,000 is typical). Are "flash hard
drives" any more durable?


Cordially,
John Turco <[email protected]>

 

[Eric Gisin]

"Flash memory cards" will wear out, physically, after a comparatively
brief number of write cycles (100,000 is typical). Are "flash hard
drives" any more durable?

I already answered that. Twice. Learn to read.