Hello,

Im working on a system which uses an IDE hard drive to store large streams
of data. At the moment im writing a single sector at a time which allows me
store about 3MB a second. Does anyone have any experience of writing
multiple sectors or DMA'ing to an IDE hard drive? If so, could you give me
some advice on how to do it? According to the hard drive specification its
capable of writing 25MB/s. I guess this is only possible with DMA or multi
sector writes.

Also another quick question is: im using the hard drive with a 5V power
supply at the moment, would it work with a 3.3V supply?

Thanks for any help,

A couple of notes:

Set IDE 32-bit IO setting to ON
Set use DMA to ON

Test results of an HDD with quoted 24mb/sec r/w speeds:
(with 32bit and DMA)
Timing buffered disk reads: 64 MB in 2.81 seconds = 22.78 MB/sec

(with 16bit and no DMA)
Timing buffered disk reads: 64 MB in 14.42 seconds = 4.44 MB/sec

I am guessing this is the problem you're having. If you're using Linux then hdparm -c1 and -d1 will
sort your problem. If you let me know what OS you are using I'll try and help.

Nathan D Higgins


"O. Adema" wrote in message
...
You should never trust vendor specifications if it comes to speed, but more
then 3MB should be possable i guess
If you set the numsector register to an other number then 1 you can write
upto 256 sectors at the time. maybe that will speed it up.
And about that power issue, hard disks are very power consuming. and if i'm
correct the motor uses 12 V (and 1.1 A at startup)
so i guess 3.3 V is hardly enough. but you can build a transformer i guess.
i hope you can deliver enough Amps.

Good luck with your project



"Ed Stevens" wrote in message
...
Hello,

Im working on a system which uses an IDE hard drive to store large streams
of data. At the moment im writing a single sector at a time which allows
me
store about 3MB a second. Does anyone have any experience of writing
multiple sectors or DMA'ing to an IDE hard drive? If so, could you give
me
some advice on how to do it? According to the hard drive specification
its
capable of writing 25MB/s. I guess this is only possible with DMA or
multi
sector writes.

Also another quick question is: im using the hard drive with a 5V power
supply at the moment, would it work with a 3.3V supply?

Thanks for any help,