Thanks Bill, nice read. Did you get your RK11/RK05 up and running on the 11/05? My 11/05s both have the low profile side mounted chassis, which I find makes them nice and compact, but limits their expansion without another cabinet.
--tom On 6/13/21 3:59 PM, Bill Degnan wrote: > It's no gunkies but I wrote up a few notes about my 11/05 variants and > support issues here: > https://www.vintagecomputer.net/digital/ > <https://www.vintagecomputer.net/digital/>. > > Bill > > On Sun, Jun 13, 2021, 4:44 PM Tom Uban via cctalk <cctalk@classiccmp.org > <mailto:cctalk@classiccmp.org>> wrote: > > I am working on the first of my two 11/05s. Interestingly, it has the > early version M7261E Control > Logic & Microprogram board and the later version M7260 Data Paths board > (with circular baud rate > selector switch) as described in: > > http://gunkies.org/wiki/KD11-B_CPU <http://gunkies.org/wiki/KD11-B_CPU> > > >From the description there, it seems like an older/newer combination, > but maybe that was > common. I > would not have guessed that the four possible combinations would all work > together, but maybe > they do? > > I have a couple different drawing sets for the 11/05 and while some have > the matching M7260 > schematic, only the GT40 drawings (I found on bitsavers) has the M7261E > schematic: > > > http://www.bitsavers.org/pdf/dec/graphics/VT11/GT40_Graphic_Terminal_Engineering_Drawings_Feb73.pdf > > <http://www.bitsavers.org/pdf/dec/graphics/VT11/GT40_Graphic_Terminal_Engineering_Drawings_Feb73.pdf> > > The GT40 drawings has the PROM listings and related, so I am hoping that > they match what is in the > two boards. > > Presently, the machine sometimes runs relatively well and other times it > does not. It does > have bit > 1 stuck ON in memory, but that should be a relatively simple task to > diagnose as it is not > intermittent. When the machine is "working" I am able to deposit 0777 at > 0100 and run. When > running > this simple program, I've experimented with flexing the boards and such, > so it doesn't seem > like an > obvious poor connection, but that remains to be seen. > > The machine is a configuration #2 model (as described in the "gunkies" > site) and my initial > messing > with KM11 boards, reveals that I can step the microcode with a KM11 in > either the #1 or #2 > position, > but when two KM11s are installed at the same time, they do not function > properly together. Is this > expected or do I have an issue there too? > > Thanks much to those who have provided details and documents on the web, > they have already been of > great value and will most certainly continue to be a resource in the > future. > > More updates in the future... > > --tom > > On 5/6/16 5:32 PM, Noel Chiappa wrote: > > > From: Mattis Lind > > > > > Thanks Noel for sorting this out. > > > > Eh, de nada. But thank you. > > > > > > >> I wonder if the ucode in the two versions is identical? The uROM > chip > > >> numbers should give it, (if they are the same on both versions, > albeit > > >> in different locations on the board), but I have yet to check. > Does > > >> anyone happen to know? > > > > OK, so the situation here is pretty complicated. To start with / make > things > > worse, that CPU uses lots of PROMs. Lots and lots and lots and lots of > PROMs. > > > > For the data paths board (M7260), both major versions appear to contain > the > > same PROMs (going by the DEC part numbers), but the chip location (Exx) > > numbers are all different. > > > > For the control board (M7261), the C, E ('early' version) and F ('late' > > version) etch revisions each contain mostly the same PROMs, but > apparently > > with slight differences between the sets of PROMs in each (as reflected > in > > different DEC part numbers). For details see: > > > > http://gunkies.org/wiki/PDP-11/05#Control_PROMs > <http://gunkies.org/wiki/PDP-11/05#Control_PROMs> > > > > to which I have just added all the gory details. > > > > As to getting the contents of all of them dumped in machine-readable > form - > > oi vey! > > > > > > >> on the earlier version (prints for that version are in the GT40 > prints > > >> online > > > > It turns out that I have hard-copy prints for the "C" etch revision of > the > > M7261, which do not yet appear to be online; the GT40 prints have the > "E" > > etch revision. > > > > I will scan the pages for that revision of the board, and put them up > 'soon'. > > (I'm not doing the whole print set, it's about 1" thick, and most of > them are > > for other things anyway, like MM11-L memory, etc.) > > > > Noel > > >
