A question about a halfnut 41C (not CV/CX)

[Massimo Gnerucci]

I finally found one of those rare birds.

A question for those in the know...

Since these were only meant as replacement units (cf. Wlodek's "Extend Your HP-41") do you think it was conceivable for the new front to be coupled with the original back, if this was still in good shape?
I ask this since the serial number on my unit is 2152S444** (machine punched), years before halfnuts were available.

Thank you for any enlightenment!

[Didier Lachieze]

(06-23-2022 02:35 PM)Massimo Gnerucci Wrote:  I finally found one of those rare birds.

Congratulations !

(06-23-2022 02:35 PM)Massimo Gnerucci Wrote:  do you think it was conceivable for the new front to be coupled with the original back, if this was still in good shape?
I ask this since the serial number on my unit is 2152S444** (machine punched), years before halfnuts were available.

Keeping the original back makes sense as the serial number is what links the unit to the customer, and it allows to track the repair history of the unit.

Btw, does the BEEP work on your unit? I'm asking the question because on the halfnut units the piezzo buzzer is glued on the back case while on the fullnut ones it is on logic board.
So keeping the original back would mean having to stick a new buzzer on it.

[Massimo Gnerucci]

(06-23-2022 04:11 PM)Didier Lachieze Wrote:  

(06-23-2022 02:35 PM)Massimo Gnerucci Wrote:  I finally found one of those rare birds.

Congratulations !

Thanks Didier, just pure luck, of course.

(06-23-2022 04:11 PM)Didier Lachieze Wrote:  Keeping the original back makes sense as the serial number is what links the unit to the customer, and it allows to track the repair history of the unit.

Btw, does the BEEP work on your unit? I'm asking the question because on the halfnut units the piezzo buzzer is glued on the back case while on the fullnut ones it is on logic board.
So keeping the original back would mean having to stick a new buzzer on it.

Good catch.
Yes, it does BEEP.

[rprosperi]

(06-23-2022 02:35 PM)Massimo Gnerucci Wrote:  I ask this since the serial number on my unit is 2152S444** (machine punched), years before halfnuts were available.

First thing - Jealous...

Yes, this almost certainly means your unit was serviced (at some cost to the owner since any 2152S... 41C was well out of warranty by the time the HalfNut came out) and HP Service found it cheaper/easier to provide a complete new 'front half' of the machine, but continued to use the original back half, as Didier says, to retain it's original identity. It's even possible the only thing broken on the original 41C was just the posts, which would lead them to use a new front.

Of course it's also possible some prior owner played mad scientist and spliced parts of 2 different machines together, but odds of this are slim IMHO.

[Massimo Gnerucci]

(06-23-2022 04:27 PM)rprosperi Wrote:  First thing - Jealous...

(06-23-2022 04:27 PM)rprosperi Wrote:  Yes, this almost certainly means your unit was serviced (at some cost to the owner since any 2152S... 41C was well out of warranty by the time the HalfNut came out) and HP Service found it cheaper/easier to provide a complete new 'front half' of the machine, but continued to use the original back half, as Didier says, to retain it's original identity. It's even possible the only thing broken on the original 41C was just the posts, which would lead them to use a new front.

Well, I think that not every 41C on the shelf was sold as soon as delivered to the shop: maybe this one stayed there for some time before being sold...

(06-23-2022 04:27 PM)rprosperi Wrote:  Of course it's also possible some prior owner played mad scientist and spliced parts of 2 different machines together, but odds of this are slim IMHO.

However Mr Turnbull (there's a sticker on the back) had to start from a halfnut 41C anyway.

[Sylvain Cote]

My HP-41C halfnut has SN: 2411S42991, buzzer works & ROMs version are HFF.

[Massimo Gnerucci]

(06-23-2022 05:24 PM)Sylvain Cote Wrote:  My HP-41C halfnut has SN: 2411S42991, buzzer works & ROMs version are HFF.

Can't remember which of the gazillion modules I have around here I used to check ROM versions years ago. Could you point me to the right one? And a micro how-to, maybe? :)

[rprosperi]

(06-23-2022 07:46 PM)Massimo Gnerucci Wrote:  Can't remember which of the gazillion modules I have around here I used to check ROM versions years ago. Could you point me to the right one? And a micro how-to, maybe?

The 41C Diag module, which can be easily installed in a CLONIX/NoVRAM module.

I also think one of Angel's modules does this too, but can't recall which it is... but I do know it's not the AMC-OSX.

[Sylvain Cote]

(06-23-2022 10:50 PM)rprosperi Wrote:  

(06-23-2022 07:46 PM)Massimo Gnerucci Wrote:  Can't remember which of the gazillion modules I have around here I used to check ROM versions years ago. Could you point me to the right one? And a micro how-to, maybe?

The 41C Diag module, which can be easily installed in a CLONIX/NoVRAM module.

Yep! that is what I did.

I bought a Clonix-D module just to hold the two HP-41 service modules.
There is an option in Diego's Windows application that creates the above module.

SM-1C is the original service module, targeting the C, CV, memory module, card reader and 4/8K ROMs.
SM-2A is the follow-up service module, targeting the CV, CX, X-F/M, X-M, Time and 4/8/12/16K ROMs.

When I plug my module in an odd port it activates the SM-1C ROM and when I plug the module in an even port it activates the SM-2A ROM.


Once the service ROM is activated, press the minus [-] key to get the ROM ID → [ROM 0:H 1:F 2:F]

[Massimo Gnerucci]

Thank you both.

Of course I knew about the Service ROM but never managed to buy one, nor I flashed it on my Clonix/NoVRAM (since I have other use for them).

I'm quite sure there's another module for this, can't remember if one by Angel or CCD/PPC/ZenROM/Paname/...

Gotta dig into those.

[Didier Lachieze]

(06-24-2022 07:07 AM)Massimo Gnerucci Wrote:  I'm quite sure there's another module for this, can't remember if one by Angel or CCD/PPC/ZenROM/Paname

The ROM? function in the NFCROM gives the same output as the Service module.

[dmh]

There's a method of determining the ROM versions using synthetic programming and any FOCAL ROM and is listed in PPCCJ V10N10p17-18 (repeated in 'Extend your HP-41').

Loading the Service Module into a Clonix/NoV module is probably the easiest option though :-)

(06-24-2022 07:07 AM)Massimo Gnerucci Wrote:  Thank you both.

Of course I knew about the Service ROM but never managed to buy one, nor I flashed it on my Clonix/NoVRAM (since I have other use for them).

I'm quite sure there's another module for this, can't remember if one by Angel or CCD/PPC/ZenROM/Paname/...

Gotta dig into those.

[Massimo Gnerucci]

Back at home I'll probably use DISASM from HEPAX ROM (once I'll find in which 41 I put the NoVRAM in )

Or I'll just reflash the Clonix with a Service Module.

Thank you all.

[Massimo Gnerucci]

After diggin' thru all of my 41s to look for the missing NoVRAM without success, at last I found it in the second one I checked (I didn't go all the way through the case...).

Four hours in a saturday morning... :) At least I tidied up a bit.

I confirm that DISASM answered with version HFF in my sample too.

Thanks again!

[aurelio]

Hi Massimo, congratulations and welcome to the club, this could be the younger sister of your 41c "halfnut"... .
Have fun with it

[Ángel Martin]

(06-24-2022 09:07 AM)dmh Wrote:  I'm quite sure there's another module for this, can't remember if one by Angel or CCD/PPC/ZenROM/Paname/...

Try function OSREV, included in AMC_OSX and PwerCL amongst others...

[Massimo Gnerucci]

(06-27-2022 10:35 PM)aurelio Wrote:  Hi Massimo, congratulations and welcome to the club, this could be the younger sister of your 41c "halfnut"... .
Have fun with it

Thanks! And from your thread I read these quote by Geoff:

Quote:it is a rarity as was explained years ago as it is a repair of a fullnut with a halfnut that does not contain the 41CX mini board. I had my keyboard replaced twice on my 79 41C and all they did was give me a new 41C keyboard and reused my rear shell with the serial number. both repairs occurred before the halfnut was developed.

So the rear side and serial # are consistent with what they did while repairing it.

[Massimo Gnerucci]

(06-28-2022 04:38 AM)Ángel Martin Wrote:  

(06-24-2022 09:07 AM)dmh Wrote:  I'm quite sure there's another module for this, can't remember if one by Angel or CCD/PPC/ZenROM/Paname/...

Try function OSREV, included in AMC_OSX and PwerCL amongst others...

Thank you Ángel, that's it!

[rprosperi]

(06-28-2022 04:38 AM)Ángel Martin Wrote:  Try function OSREV, included in AMC_OSX and PwerCL amongst others...

Thanks Angel. I reported above it was not in OSX, as I searched (not read) the manual for both "ROM" and "VERSION" without luck, but not "REVISION", so reached the wrong conclusion. <sigh...> It's annoying too as my memory was that OSX indeed included it. The balance between instinct and research prior to answering questions here is a slippery slope....