For SCSI-gurus

[quenthal]

Hi all!

I have Cyberstorm PPC, and I'm using cybppc.device for all my SCSI-devices.All harddrives are 68-pin, as is my cable.

 I have IDE cd-rom drive, which works nicely on my AOS3.9 CacheCDFS-filesystem.

Few days ago I acquired Toshiba XM-6201B SCSI CD-Rom drive, which is 50-pin device. I decided that I should switch using completely SCSI, and drop out my old IDE drive.

So here was my plan:
Active term - CSPPC(ID7) - HD1(ID0) - HD2(ID1) - HD3(ID2) - 68->50 active converter - CD-ROM (ID4, terminated).

Finddevice finds it at cybppc.device, ID4 and I can use software eject on it.

I have created CD0 using cachecdfs, cybppc.device and ID of 4. Mounting it doesn't create any error messages, but it doesn't show the CD icon on the desktop either even when there is cd inserted in the drive. If I try to use shell to check what is in the inserted cd, requester just pops asking for to insert drive CD0...

Any suggestions?

[Acill]

You need to terminate the 50 pin dif if I remember correctly. I can look in the manual when I get home but I remember something about mixing the devices, and the CSPPC needs to be terminated as well. My devices are all 50 pin and I have active termination set like this.

Activer terminator= AT
IDE cable 50 pin = ------
68 pin cable = ++++++
Converter = Conv

AT++++CSPPC+++HD0+++HD1+++Conv+++AT(upper pins only)----CD0---AT

[Castellen]

I'm not sure about terminating narrow SCSI devices on a wide bus.

I'm running a wide device in the middle of a narrow SCSI bus here, and it needs
termaination enabled, even though it's in the middle of the chain.

Acill is correct in saying the best way to terminate a wide bus it to have an
active 68 way terminator at each end of the chain.


Though the CDrom problem sounds like it's not mounting CD0:

The CD0 file needs to be in Devs:DOSdriver
You probably worked out how to set SCSI ID and SCSI device inside CD0

Try booting with no startup and type "mount CD0:" and see what happens.  You
might need to execute binddrivers first for it to work.

If working correctly, when you type "info CD0:" it should return something like
"no disk present", unless there is a disc in the drive.

Failing that, run Snoopdos before typing "mount CD0:" and see what's going on.

[Roj]

I've just finished configuring a SCSI chain on my CSPPC much like the one
you're working with. The layout looks right, but the one thing that I
haven't seen mentioned is term power. Make sure it's supplied by one of the
drives, preferably ones closest to the ends of the chain if you have a
choice. The best little tool you can have for SCSI is a terminator with an
LED to verify that the terminator is working and has proper termination
power supplied. Also, make sure you've got the CD-ROM set to 8-bit. It won't
work in 16-bit mode.

Some HDs will claim they have active termination available via jumper, but
I've run across a few drives that don't terminate even with the jumper set.
Investing in a couple of good active terminators may help prevent problems
down the road.

Here's a great SCSI reference page:
SCSI Terminators and Standards.

Let me know if you have any other questions. I'll do what I can to help.

[Desmon]

I have created CD0 using cachecdfs, cybppc.device and ID of 4. Mounting it doesn't create any error messages, but it doesn't show the CD icon on the desktop either even when there is cd inserted in the drive. If I try to use shell to check what is in the inserted cd, requester just pops asking for to insert drive CD0...

Try typing "diskchange CD0:" (no quotes) into a shell window. If you still get the "please insert..." requester, then you know your mount command hasn't stuck.
You didn't mention exactly how you're mounting the device driver either. Is it done from your SUS using the "mount Devs:DOSDrivers/#? ~(.info)" method, or are you doing it from a commandline?

[quenthal]

Try typing "diskchange CD0:" (no quotes) into a shell window. If you still get the "please insert..." requester, then you know your mount command hasn't stuck.

CD0:?? icon flashes for a short period on the workbench, as it should.

You didn't mention exactly how you're mounting the device driver either. Is it done from your SUS using the "mount Devs:DOSDrivers/#? ~(.info)" method, or are you doing it from a commandline?

I'm using that "mount Devs:DOSDrivers/#? ~(.info)" -line on startup-sequence for mounting.

 

If (mount) working correctly, when you type "info CD0:" it should return something like "no disk present", unless there is a disc in the drive.

It returns "no disc in drive" -message, even when there is one inserted.

Termination power is not a problem.

I tried in different way too:
Terminated HD(68pin) - HD(68pin) - HD(68pin) - CSPPC(68pin) -68pin->50pin converter (with big "ACTIVE" sticker on it) - CD-Rom(50pin) - Active terminator (68pin).

No luck with that order either. I tried the CD-Rom in both terminated and un-terminated mode while using above order.

Finddevice still finds the cd-rom drive, and I can use cd-player's or anyh other soft eject for it. Could it be that the drive it self is damaged, since that it rarely makes that "speed-up noise"..? I took the drive out of case, and noticed that it makes that noise, if I move it/tilt it a little bit while running.. ?..

-q

[SilvrDrgn]

@ quenthal,
My CyberStorm MK-III SCSI bus goes like this:

68pin Active Terminator - HD(68pin) - CS-MKIII (68pin) - 68pin->50pin converter marked with "ACTIVE" - CD-RW (50pin) - Tape Drive (50pin) - CD-ROM (50pin) - Active terminator (50pin).

Using the built-in termination capability of a device, I have found, is unreliable.  Termination power is turned on for all drives that have it available.  Built-in termination capability for all devices is turned off.  Everything works fine.

A difference that I noticed on your bus is that you have a 68 pin active terminator after the last 50 pin device.  That right?  Plus, how long is the total length of the 68pin and 50pin cables added together?  Maybe it's too long.  Also, by the way you describe your drive making noises, maybe it's actually broken in some way that makes it not work with data CDs.

Hi quenthal !
 
 I've got a pretty good suggestion, how to solve your SCSI problem. The problem seems to be the 68(16 bit)->50(8 bit) pin converter. Sometimes when you use these converters, the high bits(8-15) of the SCSI bus aren't terminated properly. This results in some strange problems, where the SCSI unit replies when scanning the SCSI bus, but refuses to transfer large amounts of data(The eject command gets through, but pretty much everything else fails).

 So get a new converter that terminates the high bits properly, or find a soldering iron and do it yourself(IF YOU GOT THE KNOWLEDGE !!!).

 BTW. The active/passive termination problem, is not quite as it seems. It's easy to think that an active termination has something to do with an automatic termination  function on the SCSI bus, but no. The difference between active and passive termination, has to do with signal quality on the SCSI bus. Active termination has transistors driving the 5 Volts, where passive comes from a resistor chain. In some cases the active termination improves the signal quality, enabling longer cables and improved HF(High Frequency) properties.

 I hope this little FYI, help  you to solve this little annoying problem.

!8o)

/SpaceMan

Stil waiting for my A1 G4.

[SilvrDrgn]

@ SpaceMan,
quenthal has noted in his posts that his 68->50 pin converter is labeled with the word "ACTIVE".  When that is the case, it already has the high bit termination that you mention.  So that's not the problem.

Hi Michael !

 No, active means it uses transistors to drive the termination. Not that a plug&pray function has been enabled. I have solve the problem many times this way, both privately and at work.
 But I've seen a lot of people making this false assumption about the "active" jumpers on SCSI units, even electronic engineers. Macs are really fuzzy about this, but it sometimes comes down to how "smart" the controller hardware is. Some controllers can actually solve the problem, but it is VERY seldom.
 I'm 99.9% certain that the problem will be solved with a proper converter.

!8O)

/SpaceMan

[tonyw]

When you issue the "Mount xxn:" command, it makes no reference to the drive at that time, so no error means nothing. It doesn't reference the drive until you ask for a transfer of some kind.

I agree with Spaceman, I wouldn't trust the acitve terminator, I'd go for one of those liddle biddy ones that only terminate the top address bits.

BW, did you check that Cybertools (or whatever it is) has got "last device" set to at least 4?

tony

[iamaboringperson]

I'm using that "mount Devs:DOSDrivers/#? ~(.info)" -line on startup-sequence for mounting.

that doesnt sound good.
being in the devs:dosdrivers directory it should mount at boot time,
the command line to mount it is 'mount cd0:'

check the actuall mount list 'ie cd0'
and look in the info(using workbench) for the cd0.info line, make sure that the file system it refers to i in the L: directory and check to see if the unit id is correct