I assume your building up a Qbus PDP-11.
Yup. They're easier to get going for starters and since I got rid of the 11/44 the fastest system I've got.
To go from RQDX3 to any drive you need a distrbution panel as used in BA23 or M9058 distribution board usually used in BA123.
Yup, got one of those in the BA23. Oh, are the floppies DU0/DU1 with the disk drive DU2 or is it different?
The M9058 can plug in to any general slot in Qbus for power and does not past interrupt or DMA grant. Bottom/end of the bus is fine.
Interesting, I didn't realize the RQDX series boards didn't use interrupts or DMA. Does the CPU just poll them endlessly?
Then you need a 50 wide cable from RQDX3 to the distribution board and the cable to match floppy from the distribution board (usually 34 wide).
Got that. The floppy cable I have has a twist between the second and third plugs, but I'm using the straight section only.
Jumper details are up to you to slug out but I have two systems using the RQDX3 and M9058. I also have the Micro PDP-11 using the ba23 distribution. Don't ask right now I can not get to them for the next month. Drive jumpers have to be correct.
For the RX50's were there any jumpers? If I'm still fiddling with this in a month I might ask for a pic of the configuration.
All of this is in the various manuals but no single one!
The RQDX3 was kind of out of my price zone the last time I worked on this stuff. The ESDI controller is extremely fast (and does elevator seeks so it rocks on RSX11) but doesn't have floppy support.
I'll see if I can dig out/find any of my RQDX1 boards to cross-check the RQDX3. Any of them should be able to run a RX50 (and lord be told I have RD52 and RD53 drives around here....)
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