'Halfnut' vs 'Fullnut'


Ok, sorry to be dense here, and forgive me for being ignorant, but what exactly is a 'halfnut' vs. 'fullnut' when talking about 41's?

I tried a search here and found a picture showing the display being different - one was more 'round' than the other.

Is this the only difference?



The _real_ difference is in how the electronics are constructed. Fullnut machines have a separate PCB (separate from the keyboard PCB) with pin-through-hole chips on it -- a CPU chip, a power supply chip, several ROM and RAM chips, maybe a timer chip (if it's a CX).
The halfnuts have most of the logic built into the display driver hybrid (it contains the PSU, and all the standard memory). The only other chip is the CPU, which is surface-mounted on the back of the keybaord. There is no separate logic board. CX halfnuts have another circuit board soldered on pins across the back of the main board -- this board contains chip-on-board timer and memory ICs to give the extra functions of the CX (but note the ROM in the display driver hybrid is different too, so you can't upgrade a CV itno a CX just by adding this extra board :-().
Personally, I prefer fullnuts -- they're a lot easier to repair!


I don't know if it me but i prefer the "font" on the LCD of the Fullnut. I think the "pixels" are thicker on the fullnut no? Perhaps it's not different and i imagine it.


You're correct, the LCD segments are more closely spaced
in the FullNut version, so the characters seem thicker and
more contrasty. This is specially noticeable in the center
two segments, just compare a FullNut 'H' vs. the HalfNut 'H'.

I for once rather prefer the FullNut LCD characters
instead of
the supposedly improved HalfNut ones. True, the HalfNut
display has variable contrast and lowercase characters,
but you can't benefit from them unless you use machine
code programming, which extremely few people do or care,
while having to look all the time at thinner, less easily
readable characters (specially under some kind of
illumination where they cast shadows thicker than
themselves !) isn't worth the 'benefits'. Also, I don't like
the rounded frame instead of the clean, rectangular look
of the FullNut display.


Is the only difference the display? I mean, one has the 'rounded' edges, the other has the more square edges...

Also, why are some 41's with a dark background on the keyboard and others are light?

I saw one on ebay that had a light colored keyboard bezel...



Actually, if you're into machine code programming,
the halfnut display have much more characters
It can also adjust the contrast in software.


BUT the Halfnut can be turbo'ed to run 3x the normal speed
the halfnut gets dodgy around 80-90%.

This might be know by all but I'll share it anyway (hope I get it right) the 41 had the codename Coconut and the FullNut did not get it's name until the Halfnut was introduced (well it still has the official name Coconut as it had it in the labs, people like us changed it...).



There is no light keyboard benzel. What you saw there is an HP41 with the plastic keyboard template.

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