[comp.sys.handhelds] Hp-28c vs. Hp-28s

mm459504@longs.LANCE.ColoState.Edu (Michael Miller) (12/22/90)

After considering my several finanancial problems and the lack of 
a serious (read: better than a 41cv) calculator. It brings me to ask
the following question:

Just what is better about the 28s and just how little memory does the 
28c have? (it was mentioned in a for sale message that it had 2k, it can't
be THAT small could it? that would be like having a mercedes with a 1/4 cup
gas tank.


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mm459504@longs.lance.colostate.edu | Mike Miller | MikeL | Finger me!

jpser@cup.portal.com (John Paul Serafin) (12/23/90)

It is true that the HP28c has only 2k of RAM.   Several hundred bytes are
used by the operating system, so the maximum user memory is even less.  A
28c can be modified to add another 32k or 64k of RAM, but that is expensive
to do and does not provide the subdirectory or improved plotting of the 28s.
While having only 2k of RAM does not render the 28c completely useless, it
is completely out of balance with the rest of the calculator and severely
limits the 28s to much less than it would otherwise do with ease.  I prefer
to look at the 28c as a super-duper 15c, that is, a superb machine for hand
calculations with several quantum leaps beyond the HP15.
1. 4 line stack
2. generalized object stack
3. readable programs (much much more readable than key codes)
4. named storage locations (what is in reg 6 and does it conflict with
..                          register usage in another program)
5. incredible ease of working with complex numbers, vectors, matrices
6. open ended stack depth (item 1 should have been: 4 line DISPLAY)
The most disappointing aspect of the 28c was the implication that it was
to replace the 41 which had ports for software and i/o and that there
would be no successor to the 71.
Ironically, the 48 has expandability and i/o and is better than the 28
for hand calculations since it has more funtions that don't require
menus to access.   The 28 retains a price advantage.
John Serafin
jpser@cup.portal.com

akcs.falco@hpcvbbs.UUCP (Andrey Dolgachev) (12/23/90)

Yes, believe it or not, the 28c does only have 2k RAM.  Basically, this
means that you only have enough memory for normal operations, a few
fundamental programs,  but no games or large programas.  The other
advantage to the 28s is that it has memory functions hwihc the 28c
doesn't need and that it runs at 1mhz compared to the 28c's .8 or so.

johnt@meaddata.com (John Townsend) (12/30/90)

In article <11815@ccncsu.ColoState.EDU>,
mm459504@longs.LANCE.ColoState.Edu (Michael Miller) writes:
|> 
|> After considering my several finanancial problems and the lack of 
|> a serious (read: better than a 41cv) calculator. It brings me to ask
|> the following question:
|> 
|> Just what is better about the 28s and just how little memory does the 
|> 28c have? (it was mentioned in a for sale message that it had 2k, it can't
|> be THAT small could it? that would be like having a mercedes with a 1/4 cup
|> gas tank.

Yep, it's THAT small, and that's a good way of describing it.  Actually, as I
recall, with nothing in memory and with UNDO, LAST, and CMD disabled, it would
say there was only about 1800 bytes free.

Don't forget, however, to keep it in the context of the technology of the day
when it was introduced.  Back then, that was a phenomenal amount of memory to
have in your palm.  Other caculators were still measuring their memories in
"program steps," if they had more than one.  Not that the technology wasn't
there to give it more memory, as the 28S showed soon afterwards, but that a
calculator with more memory than that built in was just unheard of at the time.

--
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