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Solid-State Hard drive ( at least 1gigabyte )

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Newbie level 6
Mar 6, 2002
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Back in 1994 I found an articale for a 4MB solid-state hard drive in ELEKTOR/ november issue. I've been wondering if I could use 2 x 512MB dimms on a PCI card to emulate a hard drive. The card should have battery backup and be BOOTABLE. WHERE DO I START ? I will appreciate ANY input to this project and WILL make the final design available to ALL who have contributed. THANX
interested ? EMAIL:

ok the short answer is yes


but first

you need to read a little about ide

and how it "mode addresses " the bus

and the translation it employs as the mode changes

when the bios does the post
the geometery is loaded to the shadow or to the bios ram
for exicution

it then {assuming you set the details other than auto mode or it queries the controller on the hdd for the geometary string to be sent from the now loaded core on the hdd {loads to the hdd bus controller chip} once this string inisialises the bus flags
the controllers registers


mode sector tracks landing zone etc
say udma 166550 256 65535 0 ...

master bus controller reads them and sets up the mode of translations as the o/s boots
it uses a little memory array to set the flags and passes this to the post bios app that is running like an exe in its own o/s {the bios boot block}

each time {much like a modem employs the two laders and the guy in the middle approch to boot up the speeds
is how the whole of this wintendo system works}}

so.... knowing these few things is the start of a worthwhile project

why you dont just buffer an 512 mb sdram add a few batteries and a pic boot from this

i dont know

we are the borg

i know that when you plug into 133 mhz system you must be very carefull to preserve hirachy and also integrity

i guess they dont make bootable o/s onrams becouse
its a hakers paradise

lets see if you can ???

Its a real puzzle why theres
not general release of this
technology comercially.
so ready now and so good!


This company may be of interest to you:

**broken link removed**

NO! you can't. Thats dynamic ram, you need flash! Go for the usb dongle solution.
A few dedicated chips are about, like ST72F651, optomised for flash card i/f, full speed usb. I'm working on one at the moment. Enumerates as a drive, stores 64M on flash, fits in your pocket.

Whoops, didn't read your post carefully enough. U r talking about a bootable pci card.
A place to start is 'open cores', search for it with google. Open source hdl code for a pci interface you can load into an FPGA.
Place to start?

thanks for kitsune very very much
I think that if on person can make IDE storag with SDRAM that be supply it power whit battery,it will be great.

The bigest problem with your IDEA is DRAM. DRAM requires refreshing of the chips. How are you planning to do that.

You would require.
1. Patching the BIOS to read from the PCI card rather than from teh IDE interface.
2. keeping the DRAM refreshed every few milliseconds.
3. Implementing interface and dirver for motherboard.

I would suggest using a Compact Flash card connected to the IDE interface.

cf to ide

hi .. i would use compact flash .. works fine in ide mode .. for more infos see:
**broken link removed**




You can use multiple MMC or Secure digital cards with SPI interface to achieve 1GB. It is easy to use.


But still the IDE interface on the CompactFlash makes it much more easier

The best speed can be reach when you connect the CF card to IDE with PIO4 enable . Our current CF product's write spped can be as high as 4.7MB/s on PC. The read speed can be maxmize upto 10MB/s when use the USB2 card reader in true IDE mode. With MMC/SD SPI mode , it's very slow . Most of the PDA use this mode to access SD/MMC . But you lost a lot in speed .

You can get CompactFlash cards up to 1 GB. If you download the file CompactFlash2ide.rar which I have uploaded in this topic: **broken link removed** then you can interface your CompactFlash to the IDE-interface. It is very easy to connect and seems to be the best solution for your purpose.

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