On Sun, Nov 8, 2015 at 12:50 PM, Josh Dersch <dersc...@gmail.com> wrote:
> Hi all - > > As noted in a mail last week, I now have my PDP-11/05 running with working > core (8KW). I had some time last night to try loading in some "real" > software, and I started with the PDP-11 paper-tape BASIC, which I've > successfully loaded into memory (in theory). At this point, it became > clear that there's still an issue or two to iron out in the CPU; BASIC > behaves extremely erratically, spewing random error messages, listing > garbage, and corrupting itself and crashing pretty quickly. > > I'd run the memory exerciser MAINDECs previously (and I ran them again for > good measure) and there are no obvious issues with the memory. The system > exerciser diagnostic (ZQKB) passes, but the "11 family instruction > exerciser" (ZQKC) fails after a minute or so at PC=016014. > > I have the listing for the diagnostic (though I'm not precisely sure > whether it's exactly the same revision) from here: > > http://bitsavers.trailing-edge.com/pdf/dec/pdp11/xxdp/diag_listings/MAINDEC-11-DZQKC-C-D_11_Family_Instruction_Exerciser_Nov73.pdf > > The doc is pretty grainy but the code at 016012 doesn't actually seem to > match what I've got in memory (I disabled relocation in the test just to be > sure things didn't get moved around) and there's no failure check at that > particular point in memory either. > > I've tried the paper-tape images from Bitsavers as well as the ones on the > XXDP RL02 images floating around out there and they all yield the same > results; I suppose it's possible the CPU is failing in such a way as to > make the test reporting incorrect but it seems more likely that (a) I have > an outdated listing or (b) I'm misinterpreting the results somehow. > > Anyone have any experience with this particular diagnostic? > > Thanks, > Josh > FWIW - I find the MAINDEC programs frustrating to work with myself. I am also working on an 11/05, same basic stage in testing. I can load programs but I get failures eventually. The power tests accurately. I think in my case the G114 (sense / inhibit) is the issue but I am still working on it. I have a teletype set up to interact with the machine. -- Bill
