IC's for simple calculator applications?

C

Chaos Master

Guest
hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?

thanks!
--
Chaos MasterŽ | "I'm going under,
Posting from Brazil! | drowning in you
Win 98 + BB4Win | I'm falling forever,
Slackware Linux | I've got to break through"
---------------------. -- Evanescence, "Going Under"
 
Chaos Master <chaos_master@ig.com.br> wrote in message news:<MPG.1b1ddf7749e255d49899f5@130.133.1.4>...
Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?
Click to expand...
If this was a quarter-century ago, then the AMD 9511 would fit the bill.
(Well, they were never cheap, I remember them listing for $100+.)

Do you need a keyboard/display driver interface? If so, then you really
just want a caclulator chip, and you get the keyboard and display driver
and display and case for free for as little as 49 cents.

If not, you get a general-purpose CPU driven
by your computational and interface needs (precision, range, floating-point
vs fixed point vs BCD, ops/sec, etc.)

Tim.
 
Chaos Master wrote:

hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?

thanks!
Click to expand...
What are you trying to do? If you want a calculator, I suspect that
those chips are custom-made by the same folks who make calculators.

If you want a machine to do the calculations then a microprocessor (even
a little bitty 8-bitter) is going to be _much_ faster than a calculator.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
 
On Wed, 26 May 2004 00:20:11 -0300, the renowned Chaos Master
<chaos_master@ig.com.br> wrote:

hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?
Click to expand...
If you're making a calculator, with display and keyboard, then a
calculator chip is extremely cheap in high volume (and otherwise
pretty much unattainable) and will do that trick (and nothing else).

A suitable microcontroller (pretty much any of them with a few K bytes
of code memory or more) can be programmed to do those operations, and
if you use a compiler (and can live with the generally lower number of
digits and other issues associated with the calculations being done in
binary rather than BCD) you may be able to avoid much of the
programming.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
Spehro Pefhany wrote:

On Wed, 26 May 2004 00:20:11 -0300, the renowned Chaos Master
chaos_master@ig.com.br> wrote:


hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?


If you're making a calculator, with display and keyboard, then a
calculator chip is extremely cheap in high volume (and otherwise
pretty much unattainable) and will do that trick (and nothing else).

A suitable microcontroller (pretty much any of them with a few K bytes
of code memory or more) can be programmed to do those operations, and
if you use a compiler (and can live with the generally lower number of
digits and other issues associated with the calculations being done in
binary rather than BCD) you may be able to avoid much of the
programming.


Best regards,
Spehro Pefhany
Click to expand...
Or you can use a compiler and do the calculations in BCD anyway -- but
why not just buy a calculator?

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
 
Tim Wescott(tim@wescottnospamdesign.com) showed us the following results:


Or you can use a compiler and do the calculations in BCD anyway -- but
why not just buy a calculator?
Click to expand...
Just curious about what IC's are/were used for calculators.

I have plenty of calculators, and a lot of calculation software (Excel, GNUPLOT,
'bc' - Linux command-line calculator - good when I am doing stuff on a Linux
console, HP-48GX/49G calculator emulators, and others) on my PC.

[]s


--
Chaos MasterŽ | "I'm going under,
Posting from Brazil! | drowning in you
Win 98 + BB4Win | I'm falling forever,
Slackware Linux | I've got to break through"
---------------------. -- Evanescence, "Going Under"
 
Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message news:<itd9b0hvviu8ob42gg3hr7nheotdroqla7@4ax.com>...
On Wed, 26 May 2004 00:20:11 -0300, the renowned Chaos Master
chaos_master@ig.com.br> wrote:

hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?

A suitable microcontroller (pretty much any of them with a few K bytes
of code memory or more) can be programmed to do those operations
Click to expand...
I would think that a few kbytes would be enough to implement a full-fledged
scientific calculator. A 4-banger could probably be made to fit in less
than 512 bytes and the bulk of the code would be keyboard decoding and
display driving.

Tim.
 
On 27 May 2004 03:35:27 -0700, the renowned shoppa@trailing-edge.com
(Tim Shoppa) wrote:

Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message news:<itd9b0hvviu8ob42gg3hr7nheotdroqla7@4ax.com>...
On Wed, 26 May 2004 00:20:11 -0300, the renowned Chaos Master
chaos_master@ig.com.br> wrote:

hi.

Are there any cheap IC's around, to do the simple calculator operations (add,
subtract, multiply, divide, square root)? Or is a microcontroller better to do
this?

A suitable microcontroller (pretty much any of them with a few K bytes
of code memory or more) can be programmed to do those operations

I would think that a few kbytes would be enough to implement a full-fledged
scientific calculator. A 4-banger could probably be made to fit in less
than 512 bytes and the bulk of the code would be keyboard decoding and
display driving.

Tim.
Click to expand...
Sure. Reasonably tightly coded in assembler (which isn't that big a
deal for four functions plus square root). OTOH, linking in a compiler
floating-point math package and/or using printf() "can" make short
work of 4K bytes before you even touch math.h or equivalent. 8-(

In the PIC line, using assembler, the PIC16F72 (28 pins, 2K x 14)
would probably be a safe (but perhaps not optimal) choice for a
one-chip LED calculator (which could use RPN). The cheapest with 28
pins looks like the 16C55A, which would save about 38 cents in 100's
(18%) but has the 12-bit core, only 512x12 code memory, is OTP not
flash and has only 25 bytes of RAM rather than 128, and might need an
extra external part or two for the clock.

This might be a good project for a student (make an 8-digit LED
calculator with 4 functions, square root and memory, with a nice RPN
stack).

There are far fewer choices if you want to drive a typical multiplexed
LCD display and want flash. TI's MSP430 line would probably be
attractive.

An even nicer project would be to make an RPN calculator using a 20x4
VFD or organic LED display.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
On Thu, 27 May 2004 01:08:27 -0300, Chaos Master
<chaos_master@ig.com.br> wrote:

Tim Wescott(tim@wescottnospamdesign.com) showed us the following results:


Or you can use a compiler and do the calculations in BCD anyway -- but
why not just buy a calculator?

Just curious about what IC's are/were used for calculators.

I have plenty of calculators, and a lot of calculation software (Excel, GNUPLOT,
'bc' - Linux command-line calculator - good when I am doing stuff on a Linux
console, HP-48GX/49G calculator emulators, and others) on my PC.

[]s
Click to expand...
The few cheap non-programmable ones I've examined seem to use ASICs.
TI programmable calculators use CPUs (not microcontrollers). The
TI-85 uses a Z-80 and the TI-89 and 92 use a Motorola 68000. I
suppose they're always CMOS versions of the CPUs due to power
consumption. You can program the TI graphing calculators in assembler
if you want and there are a lot of programs out there. See
http://www.ticalc.org .

I've never used an HP programmable calculator but I'm curious... so
Google. Interesting, it seems HP developed a CPU for their
calculators. It's called Saturn.
http://www.rhoads.nu/bjorn/hp48/starinst.html

--
Boris
 
Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message news:<pskbb013tsgcl58mkfncdig7fn122q8dq0@4ax.com>...
An even nicer project would be to make an RPN calculator using a 20x4
VFD or organic LED display.
Click to expand...
That's sounding a lot like my HP 9100A, circa 1968. Of course it didn't
use any IC's, and used a CRT:

http://www.hpmuseum.org/hp9100.htm
http://www.hpmuseum.org/tech9100.htm

Tim.
 
Chaos Master wrote:
Are there any cheap IC's around, to do the simple calculator
operations (add, subtract, multiply, divide, square root)? Or is a
microcontroller better to do this?
Click to expand...
Spehro Pefhany wrote:
A suitable microcontroller (pretty much any of them with a few K bytes
of code memory or more) can be programmed to do those operations
Click to expand...
Tim Shoppa wrote:
I would think that a few kbytes would be enough to implement a
full-fledged scientific calculator.
Click to expand...
I should hope so! The world's first handheld scientific calculator,
the HP-35, had only 768 words of ROM. The ROM was 10 bits wide, and
one word was unused, so that was equivalent to 958 3/4 bytes.

The HP-35 did not have some features people would expect now, such as
selectable angle mode (degrees vs. radians) and engineering notation,
nor did it have hyperbolic trig functions, factorial, combinations and
permutations, and statistical functions. But it did have all the basic
arithmetic, logarithmic, exponential, trigonometric, and inverse
trigonometric functions.

Nonpareil includes a microcode-level simulator, a microassembler, and
reverse-engineered source code of the HP-35 ROM:

http://nonpareil.brouhaha.com/

Nonpareil also simulates various other HP calculators, including the
HP-45, HP-55, HP-32E, HP-33C, and HP-41C.

Currently Nonpareil runs on Linux. I've partially completed a Windows
port, which I will offer for sale once it is debugged.
 
On 27 May 2004 12:22:47 -0700, the renowned shoppa@trailing-edge.com
(Tim Shoppa) wrote:

Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message news:<pskbb013tsgcl58mkfncdig7fn122q8dq0@4ax.com>...
An even nicer project would be to make an RPN calculator using a 20x4
VFD or organic LED display.

That's sounding a lot like my HP 9100A, circa 1968. Of course it didn't
use any IC's, and used a CRT:

http://www.hpmuseum.org/hp9100.htm
http://www.hpmuseum.org/tech9100.htm

Tim.
Click to expand...
I HAD ONE OF THOSE!! Bought it used ex-JPL in a stationery store in
Downey CA (home of the oldest McDonalds in the world). Just exuded
quality from the gold-plated PCBs to the core memory. It "disappeared"
during a move, unfortunately. It still worked perfectly, especially
the keyboard, although the CRT was suffering from a bit of burn-in.

Is there any way to duplicate the quality of that keyboard in a
one-off?

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
[Since the topic is drifting that way:]

http://power48.mobilevoodoo.com/ is a port of Emu48 for the Palm that
emulates three different HP48 calculators

--
William Smith
ComputerSmiths Consulting, Inc. www.compusmiths.com
 
Boris Gjenero <enosys_at_yahoo_dot_com@no.spam.ca> wrote:
On Thu, 27 May 2004 01:08:27 -0300, Chaos Master
chaos_master@ig.com.br> wrote:

Tim Wescott(tim@wescottnospamdesign.com) showed us the following results:


Or you can use a compiler and do the calculations in BCD anyway -- but
why not just buy a calculator?

Just curious about what IC's are/were used for calculators.

I have plenty of calculators, and a lot of calculation software (Excel, GNUPLOT,
'bc' - Linux command-line calculator - good when I am doing stuff on a Linux
console, HP-48GX/49G calculator emulators, and others) on my PC.

[]s

The few cheap non-programmable ones I've examined seem to use ASICs.
TI programmable calculators use CPUs (not microcontrollers). The
TI-85 uses a Z-80 and the TI-89 and 92 use a Motorola 68000. I
suppose they're always CMOS versions of the CPUs due to power
consumption. You can program the TI graphing calculators in assembler
if you want and there are a lot of programs out there. See
http://www.ticalc.org .

I've never used an HP programmable calculator but I'm curious... so
Google. Interesting, it seems HP developed a CPU for their
calculators. It's called Saturn.
http://www.rhoads.nu/bjorn/hp48/starinst.html

The newest hp's uses an ARM processor.
Click to expand...
--


Wing Wong.
Webpage: http://wing.ucc.asn.au

FAQs about me:
Is this related to homework?
Definately not
Are you and undergrad?
Yes
Are you looking for work and do you want to work for us?
Yes, but only if it pays.
Are you insane?
No, not at the moment.
 
Użytkownik "Wing Fong Wong" <wing@tarDONTtarus.uSPAMwa.eMEdu.au> napisał w
wiadomości news:c96dfe$nd$1@enyo.uwa.edu.au...

I have plenty of calculators, and a lot of calculation software (Excel,
GNUPLOT,
'bc' - Linux command-line calculator - good when I am doing stuff on a
Linux
console, HP-48GX/49G calculator emulators, and others) on my PC.

[]s

The few cheap non-programmable ones I've examined seem to use ASICs.
TI programmable calculators use CPUs (not microcontrollers). The
TI-85 uses a Z-80 and the TI-89 and 92 use a Motorola 68000. I
suppose they're always CMOS versions of the CPUs due to power
consumption. You can program the TI graphing calculators in assembler
if you want and there are a lot of programs out there. See
http://www.ticalc.org .

I've never used an HP programmable calculator but I'm curious... so
Google. Interesting, it seems HP developed a CPU for their
calculators. It's called Saturn.
http://www.rhoads.nu/bjorn/hp48/starinst.html

The newest hp's uses an ARM processor.
Click to expand...
My HP49G uses TI cpu. You can find photos of cpu by google.

Sergio
 
Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message news:<pdicb01ogltvt5m36k4t4lu1gg0tru0pmq@4ax.com>...
It still worked perfectly, especially
the keyboard, although the CRT was suffering from a bit of burn-in.
Click to expand...
One could imagine a homebrew calculator with a vector-driven scope tube
for a display... the A/D and slope generation is trivial with modern
electronics. The Chinese make many classic round scope tubes, but
getting the funky rectangular front shape may be harder.

Is there any way to duplicate the quality of that keyboard in a
one-off?
Click to expand...
Good keyswitches aren't all that hard to come by, but the molded-in
markings that HP used are probably impossible to duplicate on a small
scale.

There may be something similar that's possible through CAD/CAM engraving
followed by a filling plastic. There are a few vendors that produce
small-quantity instrument panels using this method and what I've seen at
trade shows looks (and feels) really nice. It probably doesn't stand up
to the decades like the HP molding though.

I liked the *scale* of the HP9100's buttons. No finger can feel fat on
that keyboard. Today's GUI designers lose out by making point-and-drool
interfaces when a good button panel is vastly more efficient. (Where I
work there's a project to replace a mimic/switch panel that's roughly 8 feet by
4 feet with LCD screens... I feel it is completely misguided although it
had all the necessary buzzwords to get funding.)

Tim.
 
Boris Gjenero(enosys_at_yahoo_dot_com@no.spam.ca) showed us the following
results:

consumption. You can program the TI graphing calculators in assembler
if you want and there are a lot of programs out there. See
http://www.ticalc.org .
Click to expand...
I know TI's, but I love RPN and prefer HP's.
I consider TI's being more of small computers.

I've never used an HP programmable calculator but I'm curious... so
Google. Interesting, it seems HP developed a CPU for their
calculators. It's called Saturn.
http://www.rhoads.nu/bjorn/hp48/starinst.html
Click to expand...
HP's use CPU's, and the most recent HP-49G+ use a 75MHz ARM CPU. I've readed
that they allow you to use SD cards but I've not yet found one in any shop on my
city, so I have not looked at it. :/

--
Chaos MasterŽ | "I'm going under,
Posting from Brazil! | drowning in you
Win 98 + BB4Win | I'm falling forever,
Slackware Linux | I've got to break through"
---------------------. -- Evanescence, "Going Under"
 
"Sergiusz Roszczyk" <no_spam_s.roszczyk@elka.pw.edu.pl> writes:
My HP49G uses TI cpu. You can find photos of cpu by google.
Click to expand...
No, it's an HP CPU. It was fabricated by NEC under contract to HP.
 
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