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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: unite on July 31, 2007, 10:09:27 PM
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FInally got my Blizzard Scsi addon but am a little lost when it comes to scsi and the cables needed. I'm installing this in a tower so from the back of the scsi cable with the blizzard there is a 25pin D connector and the cd drive I have use 50pin scsi connectors (in the style of an ide conector). My problem is I've been using IDE forever and don't have a clue about scsi. I tried looking up about it but theres so many different types of connectors I'm not sure which is the correct one.
Also can I get scsi HDD and use it with the blizzard, will the amiga boot to it and is there the same limited 4gb like the ide interface.
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AmigaKit mentioned recently that they can make custom Blizzard SCSI cables. Contact them and I'm sure they'll sort you out.
Yes, you can boot. No, you don't have the 4GB limitation of the built in SCSI.DEVICE.
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The SCSI standard uses a separate earth for every signal lead, to help enhance the screening and keep cross-talk down. The 25-way D-connector simply runs all 25 earth leads into one connection. You should be able to find somewhere, I don't know where offhand, an adapter to convert that to 50-way.
Apple used 25-way connectors, and so does my SCSI I/II PC ISA interface card which came with a SCSI scanner. That uses a 25-way D plug on one end of the cable and a 50-way Centronics style plug on the other end to connect to the standard SCSI interface on the scanner. It sounds like you might need something similar, but with a 50-way IDE style connector on the other end.
You might, again I don't know offhand, find a set of pins or solder pads on the Blizzard card that could be used for direct 50-way ribbon cable connection for internal use.
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(http://www.forevermac.com/mac%20systems/25DM_50CMbig.gif)
These are the two kinds of connectors you are going to find on most external SCSI peripherals. Whatever you hook up, each unit has to have a different unit # chosen like this
(http://techpubs.sgi.com/library/dynaweb_docs/hdwr/SGI_EndUser/books/Octane_OG/sgi_html/figures/SCSI.device.dial.gif)
and the last one in the chain has to be terminated like this.
(http://techpubs.sgi.com/library/dynaweb_docs/hdwr/SGI_EndUser/books/Octane_OG/sgi_html/figures/SCSI.terminator.removing.gif)
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Yes, that's the sort of cable I have, but I don't need to put a terminator in the other socket of my scanner as it automatically terminates itself if nothing else is plugged in. My friend's Minolta film scanner does that also, it's a fairly standard function of newer equipment, and good quality older equipment too.
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Thanks for the info, is it possible to use Scsi Ultra 320 gear with the amiga. Sorry for the 20questions.
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is it possible to use Scsi Ultra 320 gear with the amiga.
I can't possibly imagine why you'd want to do that, but yes it's possible. Horrible waste of HW, though.
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If I understand this, your Blizzard SCSI card has the 26 pin SCSI block. The ribbon cable attaches, and ends with the standard DB25 (M) external connector. If that is correct, then I have located a work-around for you.
The adapter is a DB25 (F) to IDC50 (M). Just take off the bracket (2 screws). Then add a normal IDC50 (F) ribbon cable.
If you end has a DB25 (F) then you'd need a coupler.
http://www.computercablesource.com/scsi-adapter-db-25-female-with-pc-l-bracket-to-idc-50-male-external-to-internal-se-895.html
Project cost: $20 US