Subject: Re: Hard Drive standard file structure... On <02 Nov 94 12:08> [EMAIL PROTECTED] wrote:
Cs> Nope - not really. DOS evolved and Cs> evolved and it's so clunky it's Cs> unbelievable. And have *you* tried to I believe it after having one for only a couple of weeks! Good enough as somthing to just get a job done, but doesn't inspire the soul like a z80 good based machine:-) Cs> get the Docs on the low level Cs> side of the HPFS used in OS/2? It's Cs> unbloodybelievably hard. I spent Cs> a good few months tracking down the Cs> ATA standard actually (IDE design Cs> specifications). Cs> For those who want it, btw, it's in Cs> ftp.dec.com, pub/standards/ata :) Good you found it then:-) Cs> They've also got ata2, scsi1,2 and3 and a few more... Oooh, could be worth a look! >> >> It's not the size of one file that >> counts - it's the extra trouble of >> having to mess around with partitions. >> Not having to remember the drive >> letter for each file is a big plus for >> Unix IMHO. Also it would be silly >> to run out of space on one partition >> and have to start moving files here >> there and everywhere even though the disk is only 1/3 full. I know most cp/m utils write to a drive blind and generaly abort if the drive fills up but the OS does allow apps to tell the drive-space/size just apps don't bother looking! Plus cp/m flat directory structure allows files to traverse many drives, again apps just don't bother using the facility due to the extra coding needed to configure such apps to the different drive characteristics of the thousands of different drive setups. Cs> I'm considering allowing a Cs> linked-partition system, but not sure Cs> about how it'd perform speed-wise. Cs> Basically you can define two E-DOS Cs> partitions and link the data space Cs> together to form one big Cs> partition. It *may* work -- gotta look into it more. Sounds complicated! Are you designing the EDOS or whatever to be a system thats designed for the user to have consious knowledge of what the thing is doing or more a virtualised system that isolates the user from everything involved? Cs> I'm considering using the Cs> logical-sector access mode of the IDE drive Cs> to store all stuff -- other people for Cs> other partitions can use the Cs> sector/cylinder/head method if they Cs> want :) This should speed up Cs> access -- you just take the sector Cs> number in the partition, add it to Cs> the logical start of the partition and Cs> read / write... quick 'n' easy :) Hey, I missed that! Is that a logical translation feature of the low-level ATA-HD protocol or an interface layer in the host driver software? If it's the former it'll simplify the banked-uzi port I have in mind as that's designed around logical sector-sized blocks on a scsi HD:-) Johnathan. ___ Olms 1.60 [Evaluation] -- |Fidonet: Johnathan Taylor 2:2501/307 |Internet: [EMAIL PROTECTED] | | Standard disclaimer: The views of this user are strictly his own.
