MAC OS 9.2.2 SCSI question.

[sanking]

I have two scanners that need to run on MAC G4 with OS 9.2.2. They both run fine individually through an Adaptec 2906 SCSI PCI card. However, when chained, the two scanner don't appear to like each other.

OK, I have two open PCI slots on my MAC G4 Quicksilver. Could I simply install a second Adaptec 2906 SCSI card and connect each of the scanners to its own card? My intuition suggests that this should work, but ????

Any SCSI experts out there?

Sandy King

[Gordon Moat]

Absolutetly. You would then have separate SCSI buses, basically separate loops. Then the only other issue to be careful about would be software conflicts, though you can usually get around that. If either scanner needs to be initialized at start-up, like through an extension, that would be one potential conflict, even with separate SCSI buses. In other words, you would eliminate a hardware conflict, though potentially still have a software conflict. If you have the ability to only load the driver when needed, that is one work-around.

I have run such a set-up many times in the past. The worst case was several devices that did not like each other; though having them connected and not powered on solved some problems; each device only got powered on as needed.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

[sanking]

Gordon,

Thanks very much for this response. Just what I was hoping to hear.

Just wondering, would there be any way to have two different 2906 drivers and dedicate each to a different hardware card?

Sandy



Absolutetly. You would then have separate SCSI buses, basically separate loops. Then the only other issue to be careful about would be software conflicts, though you can usually get around that. If either scanner needs to be initialized at start-up, like through an extension, that would be one potential conflict, even with separate SCSI buses. In other words, you would eliminate a hardware conflict, though potentially still have a software conflict. If you have the ability to only load the driver when needed, that is one work-around.

I have run such a set-up many times in the past. The worst case was several devices that did not like each other; though having them connected and not powered on solved some problems; each device only got powered on as needed.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

[Gordon Moat]

I seem to recall some SCSI manager software, possibly Lacie or Adaptec. Basically, the software allowed switching or loading of separate devices. I am not at my office at the moment, so I don't have my OS 9.2.2 machine to check. One software I do have on that is SilverLining Pro, from Lacie, though that might only allow control over harddrives . . . it might allow bus control. Maybe surf the Lacie (http://www.lacie.com) website, or contact their tech support.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

[Henry Ambrose]

Sandy,

To make it all work now, without buying anything, you'll likely have to restart the Mac with which ever scanner you want to use already powered on to change the scanner that you are using. You can likely leave both scanners physically connected and start the Mac with only the one you want to use powered on. (you may have already discovered this) In some implementations of scsi you could hot switch and some of those switching devices and software might work on some devices like hard drives but generally scanners don't like that stuff.

Adding another pci card for a completely separate scsi bus will likely let you use both scanners powered on without scsi bus conflicts. There is some voodoo involved in scsi, so unless you test a particular configuration don't assume it will work.

If you need any, I have a lot of high quality scsi cables here and probably the Adaptec control panel that lets you run the cards. The other thing you might want scsi management is called SCSI Probe. It might run on OS 9 and might not, I don't remember now. It could have been an older system control panel.

[sanking]

Adding another pci card for a completely separate scsi bus will likely let you use both scanners powered on without scsi bus conflicts. There is some voodoo involved in scsi, so unless you test a particular configuration don't assume it will work.



I picked up another 2906 card on ebay so I will see how the two cards work together. If this allows me to work with both scanners powered on at the same time that is all I need. But as you suggest, there sure appears to be a bit of voodoo involved in SCSI, especially when it comes to scanners.

I have plenty of SCSI cables, though they never appear to be quite long enough!! Or be of the same type.

Sandy King

[Tim Lookingbill]

Make sure your termination is in order on each end of the last device on the chain and at the host card or whatever is powering the SCSI chain.

I have SCSI Probe working just fine on my 2000 Pismo Powerbook in OS 9.2.2. I use the SlimSCSI 1480 PCMCIA card. However, the card gets hot and makes the system lock up after a while when in sleep mode.

[AJSJones]

As Tim suggested, checking termination and ID's is a good start : they do have different ID #'s, yes? and you removed the termination from the middle one when adding the second in the chain, right? SCSI was great in its time (still is for some things) but ID conflicts and termination were the main issues I recall from when it first came along!
Andy

[sanking]

As Tim suggested, checking termination and ID's is a good start : they do have different ID #'s, yes? and you removed the termination from the middle one when adding the second in the chain, right? SCSI was great in its time (still is for some things) but ID conflicts and termination were the main issues I recall from when it first came along!
Andy

Andy,

Yes, I verified the termination issue and SCSI ID numbers, but one of the scanners is very sensitive to being on the chain with the other. So I decided that the best thing was to just put it on another loop, and in fact use it from another OS9.2.2 system on another partition. The issue may be more extension conflicts than a SCSI conflict since I had to also remove a handful of offending extensions that were causing one of the scanners to misbehave.

Sandy King

[AJSJones]

Sandy, I still have my twin G4 chugging along when I scan, but it's a fairly simple system (I remember extensions and Conflict Manager Ugh!) - I wasn't sure how far back your experience went. Like Henry I have a cupboard full of SCSI stuff.

So your second Adaptec, second system partition approach is working? Kind of like two different computer systems in one box!

Andy

[sanking]

Sandy, I still have my twin G4 chugging along when I scan, but it's a fairly simple system (I remember extensions and Conflict Manager Ugh!) - I wasn't sure how far back your experience went. Like Henry I have a cupboard full of SCSI stuff.

So your second Adaptec, second system partition approach is working? Kind of like two different computer systems in one box!

Andy

Andy,

I go back pretty far with SCSI. I owned one of the very first Macintoish compurters, can't remember which one it was but it was the one before the MAC+ that had a huge 128mb of RAM. And in addition to my MAC G4 Quicksilver I have a new 24" iMAC. So I am pretty much all MAC, as they say.

The second Adaptec 2906 is not yet in the computer so I can not say for sure it will work. What I am doing on a temporary basis is connecting just one scanner at a time to the one 29096 card I have installed, and of course booting into a specific system for each scanner. This is working very well, and it is what made me think that the most trouble-free environment for the two scanners would be running each from a different SCSI card. Based on my own experience with SCSI, and what others have said here, I am very optimistic that this will work.

And yes, it is kind of like have two different computers on the same platform. Or in fact, three, since I have a fully working OS10.3.9 system on another partition that I can also boot into if needed, and I use that system a lot for editing images, unless the file size is too large, in which case I transport over to the Intel iMac.

Sandy

[AJSJones]

There's never been a PC in our house. Our first at home was a 512 but at work I had a Plus with a 20MB hard drive that was non-SCSI (basically as fast as a big floppy!) Back then I was very happy to see SCSI arrive :D
Good luck with the dualSCSI cards

Andy

PS How many scanners have you tested with the USAF target? Seems like a reproducible way of assessing a key performance parameter. I've been tempted to get one but am doing OK with my DuoScan2500 so it's only be a curiosity.

[sanking]

There's never been a PC in our house. Our first at home was a 512 but at work I had a Plus with a 20MB hard drive that was non-SCSI (basically as fast as a big floppy!) Back then I was very happy to see SCSI arrive :D
Good luck with the dualSCSI cards

Andy

PS How many scanners have you tested with the USAF target? Seems like a reproducible way of assessing a key performance parameter. I've been tempted to get one but am doing OK with my DuoScan2500 so it's only be a curiosity.

Andy,

First, I should mention that I first contact print the USAF target to a very high resolution film, usually TMAX-100. The resolution of the contact negative with TMAX-100 is on the order of 140-180 lppm, depending on developer and film. Then I use the contact print to test the scanner. The result is about the same as if I were to test the chrome on glass target directly, but the fact that it is film makes the test more realistic since most of us are scanning film and not glass plates. So the results, while not industry standard, are perfectly valid for comparison purposes. But of course, only for resolution testing, not other factors that make scanners good or bad.

I have personally tested several Epson scanners (4870, 4990, V750) this way, and two vintage scanners that I own, a Leafscan 45 and an Eversmart Pro. The Leaf and EverSmart give resolution at a very high percentage of stated, well over 90% for both, whereas the effective resolution of the Epsons is about 50% or less. But of course the Epson are very easy to use, and for LF film give good results up to 3X-5X.

Sandy King

[sanking]

OK, here is the definitive answer to my question that began this thread.

Today I received the new Adaptec 2906 SCSI card. It came in a sealed box, and the card itself was sealed in a static bag. This of course I took as a good omen. I could also tell that the card was made in the good old days because the card was accompanied by several instructional booklets, two in full color, and a driver for the card on both floppy disk and CD.

So I shut down the G4, unplugged the power cord, and opened the back. Then I installed an anti-static ring on my left arm and connected it to the power supply. As a safety precaution I also touched my right hand to the power supply. Then I opened the anti-static bag, carefully withdrew the 2906 card, and installed it in an open PCI slot. It inserted nicely, so I screwed it on at the top, removed the anti-static ring, and closed the side to the computer.

Next I connected SCSI cables from the two scanners, each directly to one of the two SCI cards in the PCI slots. I then plugged the computer back up, turned on the scanners, and powered up the computer in MAC )S 9.2.2 from one of the two installed OS 9.2.2 systems.

Complete success. When I opened system profiler both of the SCSI loops appeared, each with a device called a scanner. Next step to see if that will work from the same SCSI driver at the same time, so I opened up the applications software for both scanners. Everything still perfect so I made a couple of pre-scans. With that much success I decided to call it a day. Even if there are some conflicts down the road in running the two scanners at the same time that would be a very minor inconvenience because I would rarely, if ever, want to run more than one scanner at the same time anyway.

So that is my end to this story, and thanks to all who offered advice and suggestions.

Sandy King

[AJSJones]

Sandy,
That's good news - and a pleasant surprise things worked out as expected:)
I think I'll be using my G4 and its 9.2 SCSI for my Agfa Duoscan for a while yet - I had tried to get it to work on my G5 but gave up (Firewire to SCSI was a nasty rumor:eek: and there's no such thing as a cheap SCSI board for them) and I'm not even going to try on the next Intel Mac I get

Andy