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CMS Stack 3 Ext HDD case - dip switches? Manual?

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Hi, I recently acquired as part of a bundle of macs, a CMS external HDD case, just like this one.




It had a Aztecmonster CF adapter and 1GB card in it but I can't get the Mac to see the device.


Am thinking the dip switches on the rear of the case (which seem to impact the DB25 wiring inside the case (ID select etc?)) is the issue. (Powers up fine, Aztecmonster pwr led is on, the LED for the HDD even flickers on initially on power up) just can't be seen by lido7 or fwb etc so I think the ID selection is the issue.

NB: This is a db25 in and out box, do they need special DB25 terminators like the 50pin centronics SCSI ports on ext HDD / CD drives usually do?


Does anyone have a manual or info sheet for this old hardware?

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You will need to have the SCSI ID select (the DIP switches on the case) set to something other than 0, if you are attempting to see it from a Mac with an internal SCSI drive.  The internal drive is always 0.  If your Mac also has a SCSI CD-ROM, that is usually, but not always, 3.  The SCSI chain can only see one drive at each ID.

You might want to check that the ID DIP's wires are attached to the right part of the Aztecmonster.  Or - check with Artmix whether the ID is set on the device itself instead.



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Ta, am aware of the ID issue, but both the box and the board have ID settings it seems, so that might be in part the issue, if they differ!.


While I agree "You should provide termination" the AztecMonster has "active termination" per Artmix' site/ebay listing - which I take to mean I don't need a plug/terminator in the second DB25 pin.


The instructions for the AztecMonster suggest there's a 'TRM' (termination) jumper on the card as well as 3 jumpers to set the ID (i.e. Jumpers "1", "2" &"4" giving the 8 ID combinations for SCSI). Interestingly, for some reason Artmix' PDF suggests that "1" is Termination and "T" is 1!!!  I think something was lost in translation here and that his instructions are around the wrong way - anyone agree with that or is the jumper marked "T" truly ID=1!!!! and not turn off active termination (which would explain the lack of a second, unterminated cable/plug in the second DB25 causing issues.


No straightforward combination of the DIPs (on rear of CMS) and Jumpers (on AztecMonster), or even unplugging the cable that comes from the Dip Switches into the 25pin cables, seems to work at this stage, though not tested all possible (50? combinations).


Any help greatly appreciated! 

Edited by TimHD
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I think I've mentioned this in two other threads that came up but half of the dip switches are not used. I believe the first three were used to set the ID and the last one either toggled parity or termination/termination power. It's just a really, really stupid way of substituting a proper ID selector switch and a toggle switch.

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