On Tue, Jul 16, 2019 at 4:10 PM Mark J. Blair via cctalk < [email protected]> 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 <[email protected]> > 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
