A problem with 'pi' in User mode...

[chale44incolo]

Hello all, and thanks for being here! I'm a 1984-to-present user of an HP41CV that is like an extension of my own hand...
So I have an odd problem with it, sorry if this isn't the right place to post this, let me know if so and I'll correct that. So suddenly (I believe), I have a problem where I can't enter 'shift-pi' in User mode. It declares "Data Error", and if I press for more info, it shows, "XROM 03,46" and then "NULL". Is there a way to get out of this situation? The machine has no plug-ins attached, etc. I have had it way the heck apart just yesterday, trying to remedy a springy-contacts continuity problem that erupts every few years. So it may have something to do with that, eh...but I did seem to get the machine back to working perfectly; well, except of course for this business with 'pi' in User mode.

I have a beautiful 41 emulator on my iPhone, and it doesn't do this (nor did my actual 41 until...all the sudden, it seems); I can input 'pi' to my heart's content in User mode, on the emulator, no problem. On it, I see "PI" and then "NULL" if I continue to press the "0" button. That's normal, I have to believe, eh.

Thanks much--Charley Hale, Lafayette CO USA

[Monte Dalrymple]

(11-14-2018 09:00 PM)chale44incolo Wrote:  Hello all, and thanks for being here! I'm a 1984-to-present user of an HP41CV that is like an extension of my own hand...
So I have an odd problem with it, sorry if this isn't the right place to post this, let me know if so and I'll correct that. So suddenly (I believe), I have a problem where I can't enter 'shift-pi' in User mode. It declares "Data Error", and if I press for more info, it shows, "XROM 03,46" and then "NULL". Is there a way to get out of this situation? The machine has no plug-ins attached, etc. I have had it way the heck apart just yesterday, trying to remedy a springy-contacts continuity problem that erupts every few years. So it may have something to do with that, eh...but I did seem to get the machine back to working perfectly; well, except of course for this business with 'pi' in User mode.

I have a beautiful 41 emulator on my iPhone, and it doesn't do this (nor did my actual 41 until...all the sudden, it seems); I can input 'pi' to my heart's content in User mode, on the emulator, no problem. On it, I see "PI" and then "NULL" if I continue to press the "0" button. That's normal, I have to believe, eh.

Thanks much--Charley Hale, Lafayette CO USA

A function is assigned to the pi key. To cancel press:

GOLD ASN ALPHA ALPHA GOLD PI

[chale44incolo]

Hi all again,

Well, I decided to execute the legendary 'reset everything' maneuver, i.e. OFF>left arrow down>ON>OFF>left arrow up, and behold, my pi entry problem in User mode went away. So did all my programs of course, but I'd just begun the process of getting everything back on there after my, shall we say, invasive repair activities yesterday, so no big deal. Again, thanks for hosting this great site and providing a place for people like myself to come and complain : ) --Charley in Colorado
--by the way, I'm coming closer and closer to the 'blunt instrument' continuity repair procedure on my 41CV, that is, ditching the crazy little foam-filled nano-wire PC board contactor, and getting on with hard-wiring the boards together with 30GA wire I've already bought for that purpose a couple of years ago...but I keep just barely getting the guy to 'go stable' again for many months at a time, until it suddenly quits on me yet again. At this point I've replaced/reinforced both the top and bottom plastic bosses for the case screws with custom aluminum pieces, which worked great, though clearly I am still having sporadic issues with continuity, regardless. But it's worth the battle!

[chale44incolo]

Thanks, Monte, very interesting and definitely going on my cheat sheet of 41CV tips and such. You'll see later I think via another message I just posted on the topic, that I went ahead and reset the whole 9 yards, and that did indeed remedy the issue. But I'll certainly keep this key sequence in mind and in fact I'll try it on some User key to see how it works. Thanks again--Charley

[burkhard]

(11-14-2018 10:48 PM)Monte Dalrymple Wrote:  A function is assigned to the pi key. To cancel press:

GOLD ASN ALPHA ALPHA GOLD PI

Monte is quite right of course, but as a word of further explanation, it's behaving as if
1. You had a module plugged in at one point,
2. Then assigned that key (in USER mode) to a function on the π key.
3. Then unplugged the module without removing the key assignment.

So you pressing the key is trying to execute a function assigned to the key, but the function isn't available anymore because its plug-in ROM was removed. The XROM 03,46 indicates that it is function #46 on one of the several modules that has an XROM code of 03. There are several modules that used code 3, but my far the most common would have been the HP Survey Pac. So if you (or some previous owner) every had on in the calculator and assigned a function to the π key, that would explain it.

But, it sounds like the batteries have been out a bunch of times which should have cleared those assignments. So, it's a little unclear how that one is still resident.

In any event, Monte's vice on how to clear it will do the trick.

[Valentin Albillo]

(11-14-2018 09:00 PM)chale44incolo Wrote:  So suddenly (I believe), I have a problem where I can't enter 'shift-pi' in User mode. It declares "Data Error", and if I press for more info, it shows, "XROM 03,46"

XROM 03,46 is most likely some function from HP's Surveying Pack (Survey 1B) ROM which has been assigned to the shift-Pi key for quick execution in User mode.

If you (or someone else) didn't assign it (which usually would require the Survey ROM to be plugged in some port, though it can be achieved by synthetic means) then it's possible that some manipulation you did somehow corrupted RAM, in which case perhaps a master clear would be in order to avoid further collateral effects like some other yet unnoticed weird assignments or corrupted programs and/or data.

Also, welcome to the forum.
V.

[rprosperi]

(11-15-2018 02:36 AM)Valentin Albillo Wrote:  XROM 03,46 is most likely some function from HP's Surveying Pack (Survey 1B) ROM which has been assigned to the shift-Pi key for quick execution in User mode.

According to Jeremy's "Synthetic QRG", the Surveying Pac only had functions within the range 03,00 - 03,32, and there are no other XROM 03,xx ROM Pacs listed, so most likely this was an assignment left over from some 3rd party ROM. But as noted above, the original source doesn't matter and it is easily removed as described.

[Ken S]

A fair number of aftermarket survey roms used xrom 03 for their first page. Some of these had autostart functions which defined the user keyboard when first inserted. Others had programs meant to be run by the user when first inserted which would create key assignments.

[chale44incolo]

Valentin,
Thanks. Yep, I must have somehow inadvertently caused that surveying-related function to show up on that key, no idea how. I've never had a surveying module plugged into this guy, so it didn't get there via that route! Anyhow, I'm totally good now and have all my programs back on there, and it's still being electrically "stable" as well. Those foam-filled (foam-SET, with enough decades of life!) contactor dealies are in my opinion the Achilles Heel of the 41 design, seriously. Ah well. I'll keep the soldering iron in the drawer for now, heh.
Charley