vanaards%t7@uk.ac.man.cs (01/18/91)
I've got an old 5 1/4" 13MB (10MB) Hard disk drive, taken from an old Sharp MZ5600-A. Does anyone know whether or not it is possible for this drive to be used in the Archimedes - I have a SCSI i/f and the ST506 i/f. The Drive has a make code DK503. Secondly, what drives can I use with the Archimedes. When looking down lists of Hard disks in the PCW, you generally see ST numbers, and possibly type of drive such as RLL,SCSI,IDE, etc, how do I know which will work with the Archimedes - I've only seen one ST506 ! That leads onto my final question about Hard Disks, what makes an RLL drive different from a SCSI drive - in terms of internal Hardware ? I have previously assumed that the RLL has an interface which compresses the data going to the disk, and this i/f sits as a front end to the standard drive i/f which actually does the controlling of the heads. +--------------------------------+-----------------------------------------+ | ()()TEVEN () | | | () ()() | | | ()() () ()AN () () | | | () ()() ()()()() +-----------------------------------------+ | ()() () () ()ARDT |JANET E-mail : vanaards@uk.ac.man.cs.p4 | +--------------------------------+-----------------------------------------+ +--------------------------------+-----------------------------------------+ | ()()TEVEN () | | | () ()() | | | ()() () ()AN () () | | | () ()() ()()()() +-----------------------------------------+ | ()() () () ()ARDT |JANET E-mail : vanaards@uk.ac.man.cs.p4 | +--------------------------------+-----------------------------------------+
as@castle.ed.ac.uk (A Stevens) (01/19/91)
In article <1991Jan18.151427.23894@cns.umist.ac.uk> vanaards%t7@uk.ac.man.cs writes: > > I've got an old 5 1/4" 13MB (10MB) Hard disk drive, taken from an old >Sharp MZ5600-A. Does anyone know whether or not it is possible for this >drive to be used in the Archimedes - I have a SCSI i/f and the ST506 i/f. >The Drive has a make code DK503. If it has a proper ST506 interface and you can find out heads/sectors/ cylinders - Yes! (I would be very surprised if an old 10M drive were not ST506). > > Secondly, what drives can I use with the Archimedes. When looking down >lists of Hard disks in the PCW, you generally see ST numbers, and possibly >type of drive such as RLL,SCSI,IDE, etc, how do I know which will work with >the Archimedes - I've only seen one ST506 ! The built-in A400 interface will handle winchesters that use MFM encoding over the ST506 (sometimes called ST421 I think) interface. SCSI drives *should* work with a SCSI interface, but I gather there are sometimes annoying deviations in the precise way drives respond to commands over the SCSI bus. I am no expert on this latter point. > That leads onto my final question about Hard Disks, what makes an RLL drive >different from a SCSI drive - in terms of internal Hardware ? I have previously >assumed that the RLL has an interface which compresses the data going to the >disk, and this i/f sits as a front end to the standard drive i/f which >actually does the controlling of the heads. > SCSI drives attach to a proper interface bus over which they accept quite high level commands of the ``get me this sector'' kind. RLL drives are just drives that use the old hacky ST506 interface (named after the Shugart drive that introduced it), but with the data recorded onto the disk (and sent to the controller which does the bit level clock separation and decoding) using the fancier RLL encoding scheme rather than the original MFM. Internally - at the platter and analogue level - RLL and SCSI drives differ not one whit, it is only the interface board that differs. Mind you not all drive mechanisms can do RLL - it requires rather more bandwidth than the simpler MFM encoding scheme. Wether or not a SCSI drive uses MFM or RLL or whatever internally is invisible due to the high level nature of the SCSI bus. Andrew
altman@tharr.UUCP (Hugo Fiennes) (01/21/91)
I'm probably slightly out on a few of these, so correct me if I'm wrong: ST506 interface (as supplied is on a400 series) is 5Mbit transfer rate from drive to controller. RLL interface privides approximately 1.5x the storage capacity of a ST506 drive by using a (2,7) cosing scheme (or something like that!). RLL drives have a transfer rate of 7.5Mbit/sec IDE is a PC standard for a cheap drive, it's much like a simplified SCSI bus, hence lower cost. The Archimedes 'ideA' hard disk interface provides IDE interfacing for the Archimedes, allowing internal 2" IDE drives to go into an a3000! SCSI devices sit on a SCSI bus on which there can be 8 devices (inc computers, drives, etc). High level commands are sent requesting sectors, etc and the data is returned. Fast transfer rates (with SCSI-1) of 2Mbytes/sec in async mode are possible. Hugo -- Hugo Fiennes --------------------------------------------------------------- -- "HAL, you're not IBM compatible..." ------------------------------------------------------------------------------- <-- tharr *free* public access to Usenet in the UK 0234 261804 -->
d9015t@colman.newcastle.ac.uk (J.P.O'Broin) (01/24/91)
*>In article <1991Jan18.151427.23894@cns.umist.ac.uk> vanaards%t7@uk.ac.man.cs writes:
*>
*> Secondly, what drives can I use with the Archimedes. When looking down
*>lists of Hard disks in the PCW, you generally see ST numbers, and possibly
*>type of drive such as RLL,SCSI,IDE, etc, how do I know which will work with
*>the Archimedes - I've only seen one ST506 !
*>
*>Andrew
IDE stands for Integrated Drive Electronics
This basically means that the drive has most of the controlling hardware
on board , and hence only needs a simple controller card to talk to it
Ian Copestake software make a controller card (110 +VAT), and you can fit
your own hard disk, or you can get the hard disk off them at the same time.
( 349 +VAT for 40MB).
I've just bought one for my 310 the other day, and I'm very please.
Any questions - mail me direct :
J.P.O'Broin@uk.ac.durham (drop the ' if it causes problems)
Jason.