[G4] (no subject) How to use multiple drives.

[Philip J Robar]

On Jan 18, 2007, at 11:50 AM, Steve Goldstein wrote:

> ... One drive was to be designated designated "master," and the  
> other one "slave." That was mainly in the PC world.

This has nothing to do with PC vs Mac. All Parallel ATA devices are  
either designated as master or slave, or more correctly device 0 or  
1, regardless of the method used to derive that designation.

> Another implementation just left them both as "cable select."

Cable select was not "another implementation". It has always been  
part of the ATA spec. It was however optional in
ATA 1 and 40 wire cables are not required to implement it.

> I believe, but am not really sure, that most Macs support cable  
> select.

Apple has not always "supported" cable select and not all 40 wire  
cables implement it, but if you use an 80 wire cable (which is  
required to implement cable select) in any machine that supports OS X  
then cable select should work.

> Each drive will have different jumper configurations (meaning how  
> you use tweezers and a magnifying glass to place a little short- 
> circuiting jumper onto two pins on one end of the drive) to make  
> the drive recognizable as master, slave or cable select

Yes.

> (other choices also exist for many drives).

This would be mainly (older?) Western Digital drive which had to be  
jumpered as a single drive if they were the only drive on the cable.

> I also believe that if your Mac supports cable select, you could  
> also use the master/slave config, as long as one is master (may  
> have to be the furthest connector from the mother board on the  
> cable) and the other slave.

If you jumper your drives as 0 and 1 they are 0 and 1 regardless of  
the position they occupy on the cable.

See http://en.wikipedia.org/wiki/Advanced_Technology_Attachment and  
the even more detailed article at http://www.storagereview.com/guide/ 
guide_index.html for more information on IDE/ATA drives than you  
probably want to know.


Phil


Phil
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