On Jun 7, 2009, at 9:08 AM, insightinmind wrote:

> Note: Contact your device manufacturer or consult the manufacturer’s
> website to
> determine if your device is set for cable select mode. Before
> installation, set the device to
> cable select mode if the manufacturer hasn’t already done so.
>
> Maybe that's the problem ...

Maybe not.

The Macs from B&W on use a cable which is laid out as if it were  
cable select, but the Mac still uses master and slave during regular  
operations.

The optical bus is also laid out for cable select, but the optical  
drive is always set for master, and the Zip, if present, is always  
set for slave. A hard drive may be substituted for the Zip drive on  
all models, provided that hard drive is set to slave.

In this way, the buses may accommodate devices which are faster or  
slower than the rating of the respective bus.

When the Mac is initially powered-on, each bus is put in cable select  
mode and a special reset sequence is issued to each drive.

The presence of absence of a drive may thereby be determined, also  
the mode in which the a drive is capable of communicating.

The firmware sets the ATA chip to the lower of the drive's maximum  
speed mode and the ATA chip's maximum speed mode.

In this way, ATA-6 drives (such as a fast hard drive) may be  
installed on an ATA-4 bus, and likewise an ATA-2 drive (such as a  
slow optical drive) may be installed on an ATA-3 bus.

After the ATA chip and the drives have been set-up, the Mac reverts  
to master/slave mode.



--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed Low End Mac's G3-5 List, a 
group for those using G3, G4, and G5 desktop Macs - with a particular focus on 
Power Macs.
The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette 
guide is at http://www.lowendmac.com/lists/netiquette.shtml
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/g3-5-list?hl=en
Low End Mac RSS feed at feed://lowendmac.com/feed.xml
-~----------~----~----~----~------~----~------~--~---

Reply via email to