geremin@decus.com.au (Big John from MEGATRONICS) (06/07/89)
Hello World, I am about to connect up a RM03 disk, an RM05 disk and a RM02 drive all on the same MASSBUS Controller on a PDP-1170 running RSTS v8.0. I realize that the RM02 was intended to operate on a RH11 controller on the Unibus of smaller PDP-11s with a slower transfer rate. I have them on hand and cant afford to get them converted. And I dont mind the slower transfer rate. My question is: Does anyone know if there are any problems with this config.? Thanks in advance, John G. geremin@decus.com.au --------------------------
craig@csdvx0.accu.csd.unsw.oz (Craig McGregor) (06/07/89)
In article <217@decus.com.au>, geremin@decus.com.au (Big John from MEGATRONICS) writes: > Hello World, I am about to connect up a RM03 disk, an RM05 disk and a RM02 > drive all on the same MASSBUS Controller on a PDP-1170 running RSTS v8.0. > > I realize that the RM02 was intended to operate on a RH11 controller on > the Unibus of smaller PDP-11s with a slower transfer rate. I have them on hand > and cant afford to get them converted. And I dont mind the slower transfer > rate. > > My question is: Does anyone know if there are any problems with this config.? > > Thanks in advance, John G. geremin@decus.com.au > -------------------------- We once moved an RM02 from a PDP-11/40 with RH11 to a VAX-11/750 with RH750 and RM80 and it WORKED!! I think that a jumper on the massbus board under the RM02 had to be moved to alter some timing thing. -- ----------------------------------------------------------------------- Craig McGregor (Faculty of Architecture, University of NSW) ACSnet: craig@csdvx0.accu.csd.unsw.oz Phone: +61 2 697-4764 Fax: +61 2 662-2264 -----------------------------------------------------------------------
naylor@decus.com.au (06/09/89)
In article <217@decus.com.au>, geremin@decus.com.au (Big John from MEGATRONICS) writes: > Hello World, I am about to connect up a RM03 disk, an RM05 disk and a RM02 > drive all on the same MASSBUS Controller on a PDP-1170 running RSTS v8.0. > > I realize that the RM02 was intended to operate on a RH11 controller on > the Unibus of smaller PDP-11s with a slower transfer rate. I have them on hand > and cant afford to get them converted. And I dont mind the slower transfer > rate. > > My question is: Does anyone know if there are any problems with this config.? > Several moons ago I suceeded in doing just this. DEC F/S had never seen a mixed massbus before, but they always need educating. I did it with RSX-11m+, which is a superb O/S, so what I have to offer may not work with RSTS. With RSX you have to re do sysgen and answer the question about mixed massbus. The real trick is that the last drive in the massbus chain MUST be an RM05. It has to do with the MASSBUS timing signals (I forget which ones). In our config we had the RP04s and RM02's numbered 0-4 for each set. The sequence was... RP0...RP2 RM0..RM3 RP3 MB terminator The last RP04 ensures that the bus timing is held up thru the RM02's. It took us about an hour to figure it out (by trial and error) but we succeeded and it ran well until we finally lost the 11/70. Incidentally we used an RH70 controller not the RH11. We had an RH 11 on our 11/44 but never got to try the trick out on it. Good luck !! Richard Naylor naylor@wcc.govt.nz Computer Services Manager 0530147000090::naylor Computer Services Section Wellington City Council New Zealand