Review: SCSI SCA80 drives, do they work on Amiga's ?

Buzzfuzz

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Most of you will know that running SCSI disk on an Amiga is something that requires a lot of knowledge of it to make it work properly.

Most Amiga SCSI controllers like the 2090, 2091, Oktagon, GVP HC Series all use 50 pins SCSI.

Now it's not hard to get a controller, there are enough of these offered here on Amibay and other sites.

One thing that is a bit harder to get is a good sized 50 pins SCSI disk in working condition without bad sectors.

It's also know that 68 pins SCSI drives can be used with adapters, a simple 68 pins to 50 pins will work right away most of the time.

But SCA 80 is always been left out a bit, and that is quite surprising, as these drives mostly are bigger, (a lot) younger in age, have far more cache and run at higher rpm's.

The problem is that most adapters don't have the terminators on it for the high bits therefore most believe it will not work on Amiga's.
I'm not going to do an in-depth to the workings of SCSI, Google is your friend on that in case you want to read up on this.

So I decided to have a go at the 'cheap' adapters from China/Hong Kong.
They look like this:
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I've got about 15 SCA80 drives in a short time, most sizes are 4,3GB, 9,1GB and 18,2GB, and most of them run @ 10K rpm.

I've tested in various Amiga's and controllers and I can say with a :-D that it works!

What you need is a drive that has at least the basic jumper settings on the drive itself!
If the drive is without it like certain HP drives, it won't work.

Depending on the controller you might also need an active terminator.
Most of you who have a Cyberstorm MKIII or PPC will know what I am talking about, so have a few of these at the ready also.

I've tested from a basic 68000 A2000 with a GVP HC+8 series II with 8MB to an A3000T with the onboard SCSI.
The 3000 series usually has the WDC 33C93A 00-04 chip on it.
It's better for this to have the 00 - 08 chip or the AM33C93A-16PC that LTAC usually sells if you are going to use CDROM drives also, or if you plan on using it as an external drive.

So what did I test on?

- A2000 with a GVP HC+8 Series II (Zorro 2) with 8MB, original FastROM 4.0AF, and no active terminator required
- A2000 GVP HC+8 Series II (Zorro 2) with 8MB, Guru ROM 6.10, and no active terminator required
- A3000D stock 030 onboard 12MB, WDC 33C93A 00-04, required active terminator to get drives working
- A3000T040 A3640 DKB3128 with 32MB onboard WDC 33C93A 00-08, required active terminator to get drives working
- A4000D Warpengine 4040 32MB, does not require active terminator if set on the card

I tested with various drives, from Seagate to Fujitsu to Western Digital.
Most drives work, but I did have 3 4,3GB Western Digital drives that didn't, also one HP 18,2GB didn't work either.

So my ratio has been 11 out of 15, so it's safe to say it works, but don't bet on just 1 drive, is better to buy a lot of 3 to 5 drives, or more.
You can also find these drives in old servers, so if you can get your hands on one, take them out.

To sum up, they work if you know how to work with SCSI and in some cases use an active terminator.

Pro's:

- The adapters are quite cheap, 10 of them only cost me about 22 euro's including shipping from Hong Kong
- Drives are quite cheap to get, I got some even for free and they are largely used in older servers
- Easy to setup if you have a pc with a SCSI controller and WinUAE
- Speed! in 1 case I reached 6.553MB/sec

Con's:

- Heat! these drives generate a lot of heat sometimes and in an A3000/4000D that could get problematic
- If you don't have a controller and cable, the total may be more than an IDE solution, but standard Amiga IDE will always be slower
- Size! because of the adapter, it will be a tight fit in an A3000/4000D, but it is possible

Add 1:

It might be a good idea to have some form of insulation between the adapter and the drive.

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It doesn't take much force to have the pins touching the metal casing of the hdd, and that can be poof for your controller, maybe even your Amiga :wooha:

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A great review Buzzfuzz!

Thanks for sharing, I personally use the SCA50/68 & 80 adapters, about the same cost and these work flawlessly.

I will say that the "," (comma) in the 6,553MB needs to be replaced with a "." (decimal place) or your adapter is able to read over 6GBytes per second!!!!
 
I will say that the "," (comma) in the 6,553MB needs to be replaced with a "." (decimal place) or your adapter is able to read over 6GBytes per second!!!!

That would be awesome yeah :-D but it's corrected.
 
Nice information (y)

This will help me out as I also have a number of SCA drives available :)

Well you know what to do now.

In short:
- buy a few adapters SCA80 to either 50 or 68 pins
- buy a few active terminators
- buy a SCSI controller for your pc, most pci Adaptec 19160 29160 go for little to nothing
- Set TPR jumper and ID1 > becomes ID 2 on the SCSI chain (maybe active terminator is needed depending on the controller)
- Prep the drive, I usally start in the Adaptec bios and the do a lowlevel format, then into Windows XP init the drive and then make a partition, but I don't format it
- Start Winuae, then install, partition the drive and then quick format
- If you want copy files right away, but I mostly do the setup on the real Amiga (more fun anyway)
- Install it in the Amiga, make sure you put some sort of insulation between the adapter and the drive
 
Another solution for the drives that don't have their own termination & termination power jumpers is to use them in the middle of a chain using a 68 SCA adapter and 68pin cable to join two HD units and a 50>68 cable/adaptor to connect to the controller. Of course the last HD must have both termination power and termination jumper built-in.

The problem then is using two insanely hot drives inside the same Amiga. A2000 beasts will care less about this problem.
 
I will say that the "," (comma) in the 6,553MB needs to be replaced with a "." (decimal place) or your adapter is able to read over 6GBytes per second!!!!

Not necessarily, since comma is used in most of Europe as a decimal separator. I know you brits don't, but then again you also persist in driving on the wrong side of the road. ;)
 
Tested now also on a 4000D with CS MK I and SCSI controller, works with active terminator.
 
I will say that the "," (comma) in the 6,553MB needs to be replaced with a "." (decimal place) or your adapter is able to read over 6GBytes per second!!!!

Not necessarily, since comma is used in most of Europe as a decimal separator. I know you brits don't, but then again you also persist in driving on the wrong side of the road. ;)


Well if I had to use SEK's I'd be using comma's a lot too ;)
 
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