M9301-YB Bootstrap/Terminator ROM dumps / listings?

Don North north at alum.mit.edu
Wed Apr 29 19:14:06 CDT 2015

On 4/29/2015 4:11 PM, Josh Dersch wrote:
> On Wed, Apr 29, 2015 at 3:58 PM, Noel Chiappa <jnc at mercury.lcs.mit.edu>
> wrote:
>>      > From: Jorg Hoppe
>>      > I also have a spare DL11-W to offer
>> Josh, if you want a second serial line, it's best to use a regular DL11
>> (M7800), not a DL11-W. (M7800s are available on eBay, for pretty modest
>> amounts.) The reason is that each DL11-W presents a load on the line clock
>> signal (from the power supply), even if the line clock on the second board
>> is
>> disabled; several Dl11-W's, and the line clock signal may get overloaded.
> That's good to know, thanks.  I do have a spare DL11 in my stash of spare
> boards, I just need to find it, it appears to have gotten misplaced during
> my house move last year.  Not sure if it's a -W or not.

I've had two DL11-W in my 11/34A BA11-K box for years and have never had an LTC 
I suppose if you had a a larger number (say four or more) you might possibly see 
an LTC
issue, but I never have with just two. In any event you could completely 
disconnect the
LTC circuitry on the DL11-W by removing just one inline series resistor.

>>      > From: Josh Dersch
>>      > I need to scare up a second SLU so I can get an emulated TU-58 hooked
>>      > up to try booting XXDP
>> I'm not sure any M9301 variant supports the TU-58? Some are set up to boot
>> over the console serial line, though. (I haven't yet checked the code, so I
>> don't know whether you need to feed it the absolute loader first, or if it
>> will just take .LDA files directly.)
> I'm now running off of a M9312, and there is a TU-58 boot PROM for that
> (see here: http://ak6dn.dyndns.org/PDP-11/M9312/).  I believe I have a set
> of compatible PROMs and I'll probably try that tonight, if I can find the
> time (and the DL11 :)).

The 'ZZ' (my notation) for the M9312 is also a useful addition for debug/sanity 
It goes in like a device prom, but just runs the simple M9312 console 
diagnostics and low
memory (28KW or less) memory test continuously. Image available on the link to 
my website
above, or contact me directly and I can provide a preprogrammed device. Same for 
the TU58
(or other) boot proms.


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