On 2005-05-06 14:29, Dave Foshee wrote: > > [EMAIL PROTECTED] wrote me on 5.6.05 5:58 AM. Joost van de Griek loves Macs! > >> On 2005-05-05 19:43, Fluxstringer wrote: >> >>> Termination needs to be at the end of the chain. From the factory >>> Termination is set at the CD drive at ID = 3 This becomes the dependable end >>> of the chain. >>> >>> Now , the machine will still run with drives beyond this but signals can act >>> funny. And the chain can be unstable. >>> >>> Set your drive ID to 0 or 1 or 2 with the jumper pins. Look on drive >>> manufacturers website or a drive reference website for details. >> >> That's not what "end of the chain" means. Termination needs to be at the >> _physical_ ends of the SCSI chain, ID numbers are nothing more than addresses >> on the bus. They are irrelevant to termination. > > Right. The end of the chain depends on what is in the line of the SCSI chain. > For example, the motherboard is always a 7. You want the HD as close to the > motherboard as possible, or 6. This makes access for your most used device > just a little quicker.
No. Wrong again. The ID has nothing to do with access speed, either. It is simply what it says it is: an ID. A way to distinguish between different devices on a SCSI bus. > Put your other devices at other IDs but whatever is the lowest ID, ie anything > less than 6 (if you have two devices). This is the termination. No, termination is a purely physical concept, a way to suppress signal echo on a SCSI bus. > If you have three devices, then it is the lowest number ID that gets the > termination. If you have four devices, it is the lowest device that gets the > termination. See a pattern? > > I had four devices. > > 7=motherboard > 6= HD > 5=unused > 4=external HD > 3=external CD > 2=unused > 1=unused > > In this example, 3 is terminated. It is the Terminator. That girlie man. 3 is only terminated because it is _physically_ the last device in the chain. A proper SCSI chain looks like this: [T]-[D]-[D]- [...] -[D]-[T] Where [T] is a terminator, and [D] are devices. There can be 8 devices on a SCSI bus (16 on later SCSI implementations), and their ID's and physical locations in the chain matter not one iota, as long as all devices have different SCSI ID's. The controller may be any ID you want, it is only by custom that it happens to be 7 on most Macintoshes. ,xtG .tsooJ -- Isildur: "You killed my father!" Sauron: "No, Isildur... I am your father." -- Joost van de Griek <http://www.jvdg.net/> -- PowerBooks is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! | Support Low End Mac <http://lowendmac.com/lists/support.html> PowerBooks list info: <http://lowendmac.com/lists/powerbooks.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[email protected]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/powerbooks%40mail.maclaunch.com/> iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com
