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hth · (This post was last modified: 05-28-2019 02:34 AM by hth.)

I am working on the HP-41 OS (mainframe) code to give more extended memory by extending it into page 4 and beyond (to be configurable), for a start.

There are a couple of questions that I need to ask in order to hopefully reduce problems later.

I currently assume that I can make use of previously unused areas in the module, is this a problem? Has some areas already been claimed? (I especially need the area at 0x3c00 to extend the backstep routine at 0x3b14 and the extended memory initialization code.)

As this is mainly intended for the 41CL, there is a problem with the .mod file format as it cannot handle 16-bit images. Has then been addressed in some variant of that format already? I would like to have a "MOD2" format or something that do not pack bits and allow for the turbo bits of the 41CL.

There was a desire to make this code base open source in the past, did it actually happen? It would be nice to be able to do it more in the "open"...

Didier Lachieze · 05-28-2019, 03:41 AM

(05-28-2019 02:33 AM)hth Wrote: There was a desire to make this code base open source in the past, did it actually happen? It would be nice to be able to do it more in the "open"...

I'm not sure what you mean by "open source" as the VASM listings have been published by HP as NOMAS which means anybody can use them.
Is it related to this proposal?

hth · 05-28-2019, 03:55 AM

(05-28-2019 03:41 AM)Didier Lachieze Wrote:
(05-28-2019 02:33 AM)hth Wrote: There was a desire to make this code base open source in the past, did it actually happen? It would be nice to be able to do it more in the "open"...

I'm not sure what you mean by "open source" as the VASM listings have been published by HP as NOMAS which means anybody can use them.
Is it related to this proposal?

NOMAS says nothing about the legal status. However, since I payed for those back in the days, I consider myself having the right to do this for my own purposes at least, but I am not sure about what ability I have to put it on for example Github.

No, it is not related to your link, I resurrected the source a couple of years ago and have the ability to build new OS images.

It is related to this: https://www.hpmuseum.org/forum/thread-10743.html