Conference hydra::amiga_v1

    do a dir/title="rd"  Your answer should be in there.

    I've done a dir=title=rd, drive, st, hard drive and one or two other
    but there is nothing about rd51 nor st 412 run through all notes and
    reply, slow and tedious but only way i know to find some answers.       
    
    This is why i posted .0.  I repeat that i'm not technical at all !
    
    Many thanks Patrick
    
    

>    question 1 What do i need from there to connect it to my AMIGA 500 !
 
The RD51 is an ST-506 interface drive. The only controller on Amiga I know
of that supports ST-506 directly is the A2090(a), but it is a Amiga 2000
expansison card. So here are at least 3 options:

	1. Buy one of the A500 expansion boxes that give you A2000 slots
	   (like the Pacific Peripherals thing, or the Bodega Bay (sp?))
	   Find an A2090(a) (don't think CBM makes them anymore)

	   Then you would need the cables and power a supply.

	2. Buy any of the many SCSI cardas for the A500 and buy an Adaptec
	   or OMTI  SCSI to ST-506 adapter.

	   You still need power supply and cables.

	3. Talk to John Bernard. He has built all kinds of disk expansions
	   and can probably help you out.


   
>    QUESTION 2 what is the size of the "disk" ?
 
	RD51 is 10MB.

   
>    question 3 Can i have some ram fitted somewhere ?
    
	Most of the A500 SCSI adapters allow you to plug in RAM. There
	are also many RAM expansion boards available for the A500.

john

    John,
    
    Thanks for the first input. 
    
    Is it then only a 10MB or a 100MB as if it is 10 then not worth 
    investing in perepherials... I'll rather try to find a larger disk. 
    
    RD53 or 54 i think.
    
    The RD51 is an ST-506 interface drive you said is this the top bit of my
    unit or the bottom bit just that i'm confused i always though that an
    interface was a board or something like that and here I have a board
    plus a something else that i though was a disk. 
    
    Why does it says Model st412 ?
    
    Cheers Patrick

    RD51 is a TEN (not hundred) Megabyte drive.  Unless you just want to
    play with it, IMHO it is not worth the time and certainly not the money
    if you don't already have the facility in place to simply plug it in.
    
    Tony

It's Seagate's model st412. We (DEC) bought them from Seagate and called them
the RD51.

Seagate invented the ST506 interface standard. It was originally called the
st412 due in part I think to the model name of the drives.

RD50 was the first (5mb) product with this interface, RD51,52,53,54 followed.
Now we do RZxx (SCSI) products (RZ22,23,24,55,56,57 so far)

john

    
    Well, well
    
    I will not use the RD51 as only 10MB
    
    Reading  .6 John's comments. I have now an other series of questions.
    
    Is ST or SCSI standard very different. 
    
    I'm basically looking at a 100MB drive or more. I would like to choose
    any one from DEC RD or RZ.
    
    Is One standard more trouble free once installed on an Amiga 500 ? 
    
    Are parts more available for one then the other ?
    
    Can they both autoboot ? or is this depending on the "interfaces" or
    software you use.
    
    That's all for now, Patrick 

    re: .7
    
    The ST506 and SCSI interface standards are quite different.  ST506
    operates at a lower level than SCSI, so it would be possible to build
    an adapter which presented a SCSI interface to the computer and an
    ST506 interface to the drive.  The reverse adapter would be much more
    difficult, or perhaps impossible.
    
    I have an A2090 on my Amiga.  When I got it I also bought a 40 MB
    ST506 drive with it.  I've had very little trouble with it since late
    1987.  The A2090 also has a SCSI port, and I recently invested in a
    100 MB SCSI drive.  It works fine, too.
    
    Autoboot is a function of the controller, not of the drive or its
    interface.  The A2090A sutoboots, the A2090 doesn't.
        John Sauter

All A500 interface cards are SCSI. 

SCSI is typically much higher performance thatn ST-506

If you can get a SCSI drive, get it.

john

    Re .9:
    
>   All A500 interface cards are SCSI.
    
    Actually, the A590 comes with a built-in AT drive and provides both
    interfaces.  Both the AT and SCSI connectors are present, and a jumper
    controls which one is active.  The external connector is for additional
    SCSI drives.

>   SCSI is typically much higher performance thatn ST-506
>
>   If you can get a SCSI drive, get it.
    
    I agree.  Even an AT drive is a VAST improvement over diskettes, though.

If you've just got an RD and chuffed about that, then which controller
do people recommend?

I'm toying with CHEAPHD and saw super_cheaphd.lzh on tape::.

Anyone have any good/bad comments about these?

Cheers,

Greg

    re .10,
    
    I think the jumper doesn't actually determine which one is active, but
    rather which bus the hard disk activity light on the front of the 590
    is used to represent.
    
    Mike

    Re .12:
    
>   I think the jumper doesn't actually determine which one is active, but
>   rather which bus the hard disk activity light on the front of the 590
>   is used to represent.
    
    You may be right.  Since the A590 has an internal SCSI drive connector
    in addition to the AT drive connector, it could be that both are usable
    (if you could figure out how to cram two drives into the limited space
    available 8^).  Perhaps the controller logic gives one priority at boot
    time so a formal jumper isn't needed.

Re: .13

I believe the rigid disk blocks contain boot priorities for all partitions
on a disk and that the controller looks at the rigid disk blocks for all
the drives connected to it before booting.  If I'm right, you should be
able to boot off any hard drive you want.

For the Commodore disk controllers, I believe the boot priority is hidden
under the advanced setup options for a partition in HDtoolbox (or whatever
the disk setup program is called).