On Sat, Dec 8, 2018 at 10:33 PM Guy Sotomayor Jr <g...@shiresoft.com> wrote:
> > > On Dec 8, 2018, at 8:50 PM, Josh Dersch via cctalk < > cctalk@classiccmp.org> wrote: > > > > On Sat, Dec 8, 2018 at 7:24 PM Paul Anderson via cctalk < > > cctalk@classiccmp.org> wrote: > > > >> Are you using the same pack for the 8 and the 11 > >> > > > > I connected the drive I normally use with my 11/40 to the 8/e for testing > > to help narrow down where the fault was. > > I used a 16-sector pack in all cases. > > You should be using 12 sector packs on the 11 and 16 sector packs on the 8. > > I’m actually surprised the 16 sector pack worked on the 11. > In all cases /pertinent to this discussion/, i.e. with the RK8E attached to both the 11/40's RK05 and the RK05 I've restored for the 8/e. I have 12-sector packs that I normally use with the 11/40. - Josh > > TTFN - Guy > > > > > > >> > >> On Sat, Dec 8, 2018 at 8:54 AM Bill Degnan via cctalk < > >> cctalk@classiccmp.org> > >> wrote: > >> > >>> On Sat, Dec 8, 2018, 1:02 AM Josh Dersch via cctalk < > >> cctalk@classiccmp.org > >>> wrote: > >>> > >>>> On Fri, Dec 7, 2018 at 9:58 PM Josh Dersch <dersc...@gmail.com> > wrote: > >>>> > >>>>> Hi all -- > >>>>> > >>>>> Finally got all the parts together (and my act together) to actually > >>> get > >>>>> an RK05 lashed up to my PDP-8/e -- only took a decade or so :). I > >>> fixed > >>>> a > >>>>> few problems with the RK05 and it appears to be behaving very nicely. > >>>>> > >>>>> The RK8E controller is mostly working properly but fails > >> interestingly > >>>>> when running the formatter, and during the exerciser -- on cylinder > >> 128 > >>>> and > >>>>> 192 and very infrequently on cylinder 64 it will get a cylinder > >>> mismatch > >>>>> when doing the seek. When running the formatter during the > >>> verification > >>>>> pass, on cyls 64 and 128 if I retry the read it'll continue without > >>>> issues, > >>>>> but it's never successful on a retry on cylinder 192. I tried > >> hooking > >>> it > >>>>> to the RK05 in my 11/40 and it exhibits the same behavior, so I'm > >>>> guessing > >>>>> the drive isn't at fault. And the error is consistent across packs > >> (of > >>>>> which I have only two). > >>>>> > >>>>> Apart from that fault the drive and controller seem to work fine -- I > >>>>> wrote out an OS/8 pack with Adventure on it (or at least the first > >> 191 > >>>>> cylinders of it) and it works without issue. > >>>>> > >>>>> Reading the RK8E service docs and schematics, the cylinder address > >>>> compare > >>>>> is done by reusing the CRC buffer, so I suspect the issue is in or > >>> around > >>>>> there -- the big problem is that debugging it is rather painful since > >>>> that > >>>>> logic is in the middle board of a three board set, with jumper blocks > >>> on > >>>>> top -- so bringing it out on an extender isn't an option. I'm > >> curious > >>> if > >>>>> anyone's seen this issue or is so very familiar with the logic that > >> the > >>>>> fault is obvious. > >>>>> > >>>>> I suspected the 7496 shift register at E14 which takes in the > >> cylinder > >>>>> address to be compared w/the header on disk, and I went ahead and > >>>> replaced > >>>>> it in the hopes that I'd get lucky, but no go. > >>>>> > >>>>> Anyone have any advice? > >>>>> > >>>>> Thanks, > >>>>> Josh > >>>>> > >>>>> > >>>> I'll add that during the format/verification the drive seeks properly > >>> (i.e. > >>>> it's not missing a step or overstepping), which I've confirmed by > >>> watching > >>>> the thing walk through the tracks with the cover off. > >>>> > >>>> - Josh > >>>> > >>> > >>> Partitions as rka0 / rka1? > >>> B > >>> > >>>> > >>> > >> > >
