Cable adapters for CS MKIII scsi

[motorollin]

Can anybody tell me what adapter I need to connect a 50 way ribbon to the SCSI connector on the CS?

Thanks

--
moto

[ravnen]

Something like this?




Product title:
SCSI Adapter DB68HPF/FS50 Wide CTRL/Narrow Disc

[keropi]

u need a simple device like that:

http://cgi.ebay.com/New-50Pin-to-68Pin-Internal-SCSI-Adapter-Converter-FF_W0QQitemZ120058932844QQihZ002QQcategoryZ11160QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I use a similar one, to convert a 50pin cdrom to use it with the 68pin csppc interface...

[d0pefish]

Hey,

He said he wanted to use a 50pin ribbon, so those adaptors aren't what he's asking for (although I agree using those adaptors is a better solution).

Something like this should do the job and convert the CyberStorm to 50pin. But that particular one might not physically fit, because the board goes backovers on top of the CyberStorm, by the looks of things and might be obstructed by the big capacitors.

There is a (seemingly more easily obtainable) adaptor to convert 50pin drives to 68pin - i.e. like the two mentioned above; its very small and looks like this. That way you can use a 68pin cable - IMHO probably a better solution.

If you don't plan to use any ultrawide drives, either method would work the same way. However, if you added an ultrawide hard disk in some crazy combination of two adaptors (CyberStorm converted to 50pin, and hard disk converted from 68pin to 50pin) the hard disk would be forced to work at a lower speed. :-)

If I'm wrong on any of these points, someone please jump in and correct me. :idea:

[ravnen]

The adaptors posted will work. They are intended to use on a narrow disk with a wide cable. He will just have to plug it into the narrow connector on the scsi controller instead of a disk, then he has a wide connector to use for his cable

[d0pefish]

They would work if 50pin SCSI cables were male.

Those adaptors have female 50pin connectors, 50pin SCSI cables are female too, so how would they connect...? I have one of these adaptors myself.

As I said, the first adaptor in my post does what he's asking for. The second in my post, which is the same as the one you posted, is the tidier solution and converts drives to use a 68pin cable, (the other way round, instead of converting the controller) i.e. what the CyberStorm uses as default.

[ravnen]

Hmm. My bad, to early in the morning to open my mouth

I was thinking the other way around, since my scsi has a 50 pin narrow connector.

[motorollin]

Looks like replacing the cable would be the best way, otherwise every device including the controller would have an adapter! Just so I know I get the right cable, is it a 68 way D cable I need?

--
moto

[d0pefish]

Yeah mate, that's the one.

I am using a nice rounded cable - with a bit of "arranging", it curls up reasonably well underneath the hard disk.

Don't forget you also need two proper active terminators; both ends of the chain need terminating.

Just a piece of advice, if you are going to use any SCSI ultrawide hard disks, now or in the future, AVOID Quantum/Maxtor ATLAS drives. Two died while running in my Amiga, see a huge thread that I started asking for help.

I am now using a Fujitsu model which has been superb ever since.

[motorollin]

d0pefish wrote:
Yeah mate, that's the one.

Does this one look ok? It seems to have a terminator built in!

d0pefish wrote:
I am using a nice rounded cable - with a bit of "arranging", it curls up reasonably well underneath the hard disk.

That one I linked is rounded. Hopefully it will be ok as the only other ones I can find are Akasa, which are really expensive!

d0pefish wrote:
Don't forget you also need two proper active terminators; both ends of the chain need terminating.

Doesn't the controller terminate one end? Also would the terminator on the cable I linked do the job?

Thanks for your help :-)

--
moto

[amigakit]

This is the adapter you need:

http://amigakit.leamancomputing.com/catalog/product_info.php?cPath=27&products_id=35

[motorollin]

AmigaKit roxxorzzzzzz!!!11!!!
;-)

--
moto

[stopthegop]

[qoute]Doesn't the controller terminate one end? Also would the terminator on the cable I linked do the job?
[/quote]

No.  BOTH ends need to have active "single-ended(SE)" LVD(Low Voltage Differential) terminators.  Disable termination on all devices including the controller, and terminate at the cable ends with above mentioned terminators.  That means you need a FOUR position cable to hook up one scsi hard drive, a FIVE position cable to hook up two hard drives, a SIX position cable to hook up three drives, and so on.  You need one position for the cyberstorm, two positions for a terminator at each end, and one position for the hard drive.  Add one, obviously, for each additional drive.  Make sure NEVER to hook up a "Differential" aka "HVD(High Voltage Differential) SCSI device to a cyberstorm, or any other LVD bus for that matter.  HVD uses a +5v high, LVD uses 3.3v.  Obviously icompatible, the former can destroy the latter if improperly connected on the same bus with power applied.    

[motorollin]

Thanks for the info. I had no idea SCSI terminators were so scary! :-) I've PMed AmigaKit to see if they can supply me with the correct ones, as I don't want to destroy the nice MKIII you spent such a long time packaging up :-)

--
moto

[stopthegop]

Maybe I'm a little paranoid for using excessive packing materials... ?  I did work at UPS as a teenager for one summer.  I've witnessed -- even participated in -- the abuse of parcel packages.  It ain't pretty.    

To clarify the scsi question, passive HVD terminators won't hurt anything on an LVD bus.  It just won't work.  An HVD device on the other hand, will do damage to an LVD controller and to other LVD devices that happen to be connected when power is turned on.  

The easiest way to tell the different types of SCSI is by looking at the scsi "diamond" symbol of the device in question.  A basic four sided diamond is SE "Single Ended".  If the diamond has a "carrot" (like this: "< <|>") on the outside to the left, its HVD or "Differential SCSI".  Never use such devices on a cyberstorm.  Fortunately, these are not as common.  If it has a "carrot"  on the inside of the diamond then it is what is called "LVD/SE".  This is the newest and the fastest protocol.  It is also the most tempermental.  Very sensitive to cable length, proper termination, parity errors, impedence mismatches (bent pins, etc), cable quality, etc.  These devices are great for using with the cyberstorm.  Just use the highest quality cables and keep the total lenght of the circuit as short as possible.  Max is 3M.  Thats the spec.  "Real world" Max is about 1M for best performance.  Buena Suerte Amigo!..    :-D