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Dilog DQ-614, dual-height qbus MFM controller that is supposed to emulate RL0x and RX02. Anybody tried one?

Teletech

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Jul 25, 2022
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Has anyone here had any experience with this controller?

I have a couple of these, one bare and another came with the drive. I found the manual and a diagram on bitsavers (thanks Erik and Al!) and I have it configured an a manner that makes sense. I can get to the Dilog prompt "*" but asking for a boot in lower case gets me the prompt again, in uppercase it drops back to ODT.
It could be the drive I thought went with one didn't and there's just nothing to boot so the card is working fine.
The manual describes a formatter and test utility, but it's not clear if that's in ROM or shipped as separate software. If the former than I can't seem to get it going, if the latter then I'm out of luck.
 
I had one of these a long time ago in a PDP-11/23 in a Dataram A23 chassis, with a Rodime 20MB drive, running RSTS/E. I remember it fondly; it never gave me any guff. I (stupidly) sold that system decades ago, but I was lucky to have found another DQ-614 just a few months ago. I've not installed it in anything yet.

I'm pretty sure the formatter is in ROM. One thing about booting that you might want to look at is if there's a boot ROM on the DQ-614 that may be in conflict with another boot ROM in the system.

-Dave
 
I had one of these a long time ago in a PDP-11/23 in a Dataram A23 chassis, with a Rodime 20MB drive, running RSTS/E. I remember it fondly; it never gave me any guff. I (stupidly) sold that system decades ago, but I was lucky to have found another DQ-614 just a few months ago. I've not installed it in anything yet.

I'm pretty sure the formatter is in ROM. One thing about booting that you might want to look at is if there's a boot ROM on the DQ-614 that may be in conflict with another boot ROM in the system.

-Dave
I did relocate the DQ-614 ROM address to 775000 as to not conflict with my 11/23+ boot ROM. Based on the manual, it's 22-bit address compatible.
"Controller assumes alternate address for bootstrap ROM of 175000 (must be used for LSI 11/23 plus CPU, module M8189)"-manual
I might see about replacing the11/23+ with a 11/23 in the backplane, just to see if that might change anything. Alternately, I'm tempted to try it in a different backplane in case there is something subtle I'm missing about the S-box I'm working with now.
I noticed none of the interrupt jumpers were installed (soldered-in), but I believe the manual indicates this is interrupt 4.
 
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It does if you want to emulate an RL rather than an RA. It's also a lot more flexible about what drives it will control.
But it does not handle any floppy drives, as the RQDXn controllers do.

-Dave
 
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