Don't know if you are aware of this data, might just give you some hints. http://www.ak6dn.com/PDP-11/M9312/
On Tue, Jul 16, 2019 at 4:19 PM Bill Degnan via cctalk <cctalk@classiccmp.org> wrote: > > On Tue, Jul 16, 2019 at 4:10 PM Mark J. Blair via cctalk < > cctalk@classiccmp.org> wrote: > > > I've been studying scanned documents for the M9312 UNIBUS > > bootstrap/terminator card because of reasons. They refer to Digital > > Equipment Corporation Purchase Specifications 23-000A9-01 and 23-000F1-01 > > for the PROMs, and I'm wondering whether those documents have been > > preserved anywhere? I'd love to see them. > > > > Ok, about the reasons: My PDP-11/34A has an M9301-YF bootstrap/terminator > > card, which doesn't have bootstrap code for a couple of the newer devices > > I'd like to use in the system such as RL02 and emulated TU58. The newer > > M9312 card looks more flexible for changing out bootstraps than the M9301 > > series. > > > > I'm working on getting my hands on an M9312, but I don't know yet whether > > I'll be able to get original PROMs for the specific bootstraps that I want. > > I haven't identified a trustworthy source for blank old-timey bipolar PROMs > > yet (and I'm not sure if I have a suitable device programmer for them), and > > I was thinking about making some sort of PROM emulations that I can swap > > around like they're going out of style. It would probably be helpful (and > > definitely interesting) if I could learn details about the original part > > specifications, such as what speed ratings DEC used. I don't have an M9312 > > in my hands yet, and I'm not yet sure about how rapidly the card performs > > its little 4-to-16 bit deserialization stunt. > > > > If 70ns access time parts are sufficient for the M9312's PROMs, then I may > > design an emulation with a 5V compatible 28 series EEPROM. If they need to > > be faster, then I may need to do something fancier. Or maybe I'll find the > > original PROMs that I need and then get distracted and wander off. It may > > well be easier to design a replacement for the entire M9312 card than > > trying to emulate the individual 512x4 bipolar PROMs, but since when do I > > do anything the easy way? I sure wouldn't be playing with 40 year old > > computers if I was concerned with practicality and ease of use! > > > > -- > > Mark J. Blair, NF6X <n...@nf6x.net> > > http://www.nf6x.net/ > > > Mark, > This guy makes them > https://www.ebay.com/itm/DEC-PDP-11-Boot-Prom-M9312-RL02-RX01-RX02-RK06-07-nach-Wunsch/192564377085 > > He may be able to advise answers to your questions if you find the price it > too high. > > Bill
