Curious V41 Behaviour


I don't know if it is permissible here to talk about the emulator from TOS, but since Warren doesn't offer support to it anymore I thought I would toss this out to see where it goes.

In a CV or CX setup, I add the Card Reader ROM so I can access the functions therein that support HP67/97 programs (all the ones of the form 7xxxxx). With the ROM added, if I try an XEQ or GTO to an alpha label, it won't accept the parameter. When I try to correct it with the backspace key, the emulator hangs.

This does NOT happen with a 41C setup with various ROMs added to make it act (sort of) like a CX (quad memory, extended/functions&mem, extended mem, etc....). Behaves beautifully.

I like using V41 as a testing ground for so many of the excellent RAW files out there. This is the first time I have encounter a serious bug in it.

Any comments or experiences?



Some versions of the card reader ROM actually had bugs that caused problems with entry prompts on the real calculator, though not as bad as what you describe. My vague recollection was that the most obvious problem was with "GTO . EEX" followed by a backspace, or something like that.

There also was a problem where some wand ROM revisions had problems with some mainframe ROM revisions, because the wand ROM used a mainframe entry point that moved.

It's been many years since I experienced these problems, so I may have the details wrong.

This does NOT happen with a 41C setup with various ROMs added to make it act (sort of) like a CX

What about a 41C with the card reader ROM?


What about a 41C with the card reader ROM?

Actually, that is what I meant--the card reader ROM is one of the add-ins on my Edit list.

I don't have the same parameter entry issue but I have encountered the display showing 8 zeros when I try to make and entry after ENTER. Guess I really didn't work with it much before declaring "works beautifully".

I don't seem to have any issues at all (yet) with either my real card reader (an excellent rebuilt one from plasmoid) and either of my real calcs.

I think if I am serious about porting some of the HP67 programs on this site to the HP41, it is worth the while to find alternatives or workarounds for the the various 7xxxx commands that turn up.

Many thanks,


p.s. What's new with nonpareil? I am eagerly awaiting a PalmOS version to supersede the excellent but in some ways flawed P41CX.


I made some progress toward a new Linux (and Windows) release of Nonpareil over my vacation, but now that I'm back to work and school, progress has slowed to a crawl again. :-(


You should make sure that the Card Reader ROM is installed in page 14 (the only possible page on the real machine), because the Card Reader ROM code uses absolute addresses, and will not run properly in other pages.



I think Warren gives instructions in a readme or info file about how to manually manipulate the initialization paramaters of a desired configuration. When I get home tonight I will see if I can create a profile manually, rather than from the File menu, that not only adds the desired ROM but puts it in the right place.

That all said, I am finding it is easier to not bother with the Card Reader ROM in V41 and if I want to port an HP67 program I just make the desired adjustments. I did this with the Six-Point Gaussian Quadrature routine from HP67/97 Math Pac 1, and was able to create a RAW file with HP41UC that works like a charm in V41 and Free42, and from that barcode that places the program soundly in my real HP41s. Didn't take me long at all.



Just got to check. There used to be $PAGE directive for the loading of ROM images (now MOD files in V41), but the helpfile says this is no longer supported. Don't know a workaround....



I believe that ROM files are just binary images of the module contents. MOD files have page information embedded in them, among other things, along with the ROM contents. in MODFileWin.EXE, the 'Info' function of the file menu opens the MOD file and shows you the metadata contained within it. An interesting segment of that data for the card reader MOD file is this:

PAGE: May be in more than one location
POSITION: Any page 8-F
PAGE GROUP: 0 - not grouped
BANK GROUP: 0 - not grouped

So "Any page 8-F" may be the problem. I don't know how you would modify that. The V41 source code is said to contain the format of a MOD file. So a little parsing of C code might yield the answer. (I've been too lazy thus far to dig into it.)



Yes, the MOD file was coded incorrectly, thanks for pointing that out. It was a very easy fix and I have recompiled it and posted it under The V41R8.exe install file and V41 source zip will still have the bad card-rdr for the time being since it is more work to rebuild all that.


Warren, bless you!

I was going to write you, but I didn't think you supported V41 any more and have moved on to bigger and better things. Thank you so much!


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