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Full Version: "ZENROM + 2 Memory Modules" in single X-Memory module
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I have an X-Memory module that contains a "ZENROM + 2 memory modules" in a single X-Memory module. I have all of the normal ZENROM documentation, but can't find the receipt or any info on the web about how many were made of this type. I recall it cost about the same (more?) than my HP-41CX when I bought it in the 80's. Does anyone have documentation on this item they can share?
Surely it was a custom job done by some of the handcrafts of yore, those kind of arrangements were done on demand back then. Another common configuration was X-Functions and X-Memory together, or even the Extended-IO in the HP-IL housing. I think EduCalc offered that as a service too.

Apart from the fact that both items were in the same enclosure there was nothing different to them from the stand-alone items.
Yes, I have an Edu-Calc flyer from 1991.

double module conversion was $30

triple was $55

HP-IL + either a Development, Extended I/O or Plotter was $45

It looks like they had an arrangement with S.O.S. to do the actual work. There was a 1 year warranty too.

I have an Extended Functions + 2 Extended Memory, but I don't recall if I had the S.O.S. conversion, or one of the advertised ones in the PPC Journal.

I don't recall, but I'll keep looking thru my collection, if anyone was doing modules internal to the 41 body itself. Seems like individuals have done some on there own, but I haven't found an advertised service from back then.
I recall (vaguely) a good article in the PPC Journal (I think) that was a great reference for where everything was locatable in regards to HP41 modules and how the addressing scheme worked.

Seems like a Time module could be in any port and wired to appear to the processor as though it were in any other port (maybe that applied to all modules?) there was a rule about where Extended Memory modules could go, or you had to observe that rule if they were de-cased and wired inside the calculator housing, certain modules had the same ROM numbers but I don't recall how you knew before hand which combos were bad (this was important if you wanted to put 2 ROMs in the same housing).

I'm looking through the archives here, but it is so easy distracted and wind up reading some very interesting, but not what I had actually started out looking for in the first place.
(03-04-2015 12:56 AM)TASP Wrote: [ -> ]...so easily distracted and wind up reading some very interesting, but not what I had actually started out looking for in the first place.

I hate it when that happens.
I love it when that happens.

Almost every day.

How do the curators here ever get what needs done with so much interesting stuff about distracting them away from the task at hand ??

Wish I had pulled my stuff out of storage 5 years ago, I might be up to speed now if I had.
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