This is a fairly long explanation that will explain the basics of SCSI ID #s and termination for the beginner. (We all were once!) There are also some links online that explain the same.
First, single click (highlight) your HD on the 6100. Get Info for the drive and read the line that says "Where". You will see the name of the drive, the bus# and the SCSI ID #. That is the present SCSI ID number for your hard drive. Do the same with the hard drive in your 7200. If they are different, simply move the old drive over. (I'm not familiar with the default ID #s on the 6100, but all of my 7100s had the OEM hard drive set to ID #2, while the 7200 used ID # 0 for the OEM hard drive. If they are the same, you will find (usually on the back) a row of jumpers (2 parallel rows of tiny pins.) Usually they are labeled SCSI 0, 1, 2 or some such. No pins jumpered (a little plastic piece that plugs into a pair of the pins, available from your local computer shop for a few cents or probably free if you talk nice.) equals ID #0. The ID numbers are found by adding the numbers for the jumpered pins together. Pins "0" jumpered = 1, Pins "1" jumpered = 2 and Pins 2 jumpered = 4. Jumpered Pins "0" (ID #1) and Pins "1" (ID # 2) = ID # 3, etc. DO NOT USE ID # 7 (all pins jumpered) as that is reserved for your motherboard. Now comes the fun part! You need to have only 1 device terminated in the SCSI chain. (The one located furthest from the motherboard end of the SCSI cable.) Look on the back of the 6100's drive next to the SCSI ID jumper pins and see if you have a jumper across some pins labeled "term" or TP. If so, remove that jumper. (You can use that jumper to set the ID # without having to search out another source for jumpers) Some drives have a row of 2 to 3 termination resistors located parallel to and close to the actual SCSI connector that connects to the ribbon cable in the computer. (little ceramic looking things described here at one time as looking some what like a comb for a barbie doll) These resistors can be pulled straight up removing the row of pins from their holes. (Keep them in case you later decide to terminate that drive for another application.) Removing the resistors removes termination from that drive. Be advised that I've seen a few Mac OEM drives with factory preset SCSI IDs and termination that could not be changed. If you find you have one of these, you can still use it by replacing the 7200's hard drive with the 6100's, (put the 6100's drive in the 7200's original drive bay and connect it to the same connector on the ribbon cable) change the SCSI ID and termination on the 7200's drive and reinstall the 7200's drive in the spare hard drive bay, where you had planned to put the 6100's drive. Remember that the last device physically on the internal SCSI Ribbon Cable is the only device to be terminated. If you later add external devices via the external SCSI connector, the last in that chain must also be terminated and in some Macs (The 7200 included if memory serves) you have a single SCSI chain including all internal and external devices. In this case, each device must have its own ID #, with no duplication. Some Macs have an internal SCSI Bus 0 and an additional external SCSI Bus 1. (You can tell by "Get Info" for the internal devices and "Get Info" for the external devices. If the "Where" shows a Bus 0 for some and Bus 1 for others, you have a dual SCSI Bus Mac. On these Macs, you can usually have a device on each Bus with the same ID #. (I.E. SCSI Bus 0 and SCSI Bus 1 can each have a drive with SCSI ID # 1.) I say "usually" as there are a few devices that won't allow shared ID #s such as some UMax Scanners. You can select either drive as your start up drive in the Start Up Drive control panel. (As long as the selected drive has a System installed.) It's actually easier than it sounds and doing it once makes you "expert" at adding/changing drives at will. David Allen Edwin Morrow wrote: > HI All, > > I'm pretty new to playing with > Macs. I purchased a 7200.75 > and am currently using a > 6100/60. I wanted to put the > old HD form the 6100 in the > 7200 as a second HD. I was > told providing there is room, > which there is and I seem to > have the right cables too, it > should be ok. So, I think I > have to tell the 7200 that the > old drive is no longer 01 but > 02 HD?? Not srue how to do > this? Also, when I start the > new computer with both drives, > I take it it will start with > the new HD? Will the second > HD then appear as an icon on > the screen? When I click on > it, will I then be accessing > that HD AND the OS that is on > that drive? I have 8.5.1 on > the old drive and 8.6 on the > new one. > > Thanks in advance and remember > to speak in simple terms as > I'm somewhat of a computer > idiot! :-) > > Ed > -- PCI-PowerMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | -- Sonnet & PowerLogix Upgrades - start at $169 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> PCI-PowerMacs list info: <http://lowendmac.com/lists/pci-powermacs.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/pci-powermacs%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
