Which PIC? 16F, 18F or 32?

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V G
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Which PIC? 16F, 18F or 32?

V G
Hey all,

I'm trying to build a scientific RPN calculator using a PIC microcontroller.
It will be battery powered and for use in school. I'll be using it with an
HD44780 based LCD character display and my own keypad.

Basically, I'll need enough flash and RAM on the PIC to store all the
functions a scientific calculator would have (sin, cos, tan, asin, acos,
atan, log, ln, ee, e^x, pow, sqrt and so on). As for the second requirement,
I'll need it to be as low power as possible as it will run on small
batteries.

Also, I'll be programming in C using HI-TECH's highly optimizing C compiler
for the PIC. This compiler is amazing.

I've already looked at the PIC 16F series. These seem to use low power but
I'm scared that they will not have enough flash (and possibly RAM) for my
application.
Then I looked at the 18F series. These also seem to be low power and have a
lot more RAM and flash.
I was then tempted by the PIC32 series. These chips look perfect for my
project. I'm now only concerned about the power usage of these things. Does
anyone know the power usage for the PIC32 series?

Anyway, I need advice. Which series of microcontroller should I chose for my
project?

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Re: Which PIC? 16F, 18F or 32?

Xiaofan Chen
On Fri, Dec 5, 2008 at 2:31 PM, solarwind <[hidden email]> wrote:

> Hey all,
>
> I'm trying to build a scientific RPN calculator using a PIC microcontroller.
> It will be battery powered and for use in school. I'll be using it with an
> HD44780 based LCD character display and my own keypad.
>
> I was then tempted by the PIC32 series. These chips look perfect for my
> project. I'm now only concerned about the power usage of these things. Does
> anyone know the power usage for the PIC32 series?
>
> Anyway, I need advice. Which series of microcontroller should I chose for my
> project?

http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=71281
So you have already did some study.

You can go to Microchip PIC32 website to do more research.
http://www.microchip.com/pic32


Xiaofan
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V G
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Re: Which PIC? 16F, 18F or 32?

V G
Already looked on the PIC32 site, couldn't find the power usage of the
PIC32.

On Fri, Dec 5, 2008 at 2:36 AM, Xiaofan Chen <[hidden email]> wrote:

> On Fri, Dec 5, 2008 at 2:31 PM, solarwind <[hidden email]> wrote:
> > Hey all,
> >
> > I'm trying to build a scientific RPN calculator using a PIC
> microcontroller.
> > It will be battery powered and for use in school. I'll be using it with
> an
> > HD44780 based LCD character display and my own keypad.
> >
> > I was then tempted by the PIC32 series. These chips look perfect for my
> > project. I'm now only concerned about the power usage of these things.
> Does
> > anyone know the power usage for the PIC32 series?
> >
> > Anyway, I need advice. Which series of microcontroller should I chose for
> my
> > project?
>
> http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=71281
> So you have already did some study.
>
> You can go to Microchip PIC32 website to do more research.
> http://www.microchip.com/pic32
>
>
> Xiaofan
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>



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V G
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Re: Which PIC? 16F, 18F or 32?

V G
I'm also asking in a lot of different places to get different opinions. I
don't want to make mistakes. The good people at the AVR forum showed me
roughly how much space I'll be needing, not including my own functions and
RPN logic and possible graphing features. The main concern now is the power
usage. So how much power does the PIC32 use?

On Fri, Dec 5, 2008 at 3:15 AM, solarwind <[hidden email]> wrote:

> Already looked on the PIC32 site, couldn't find the power usage of the
> PIC32.
>
>
> On Fri, Dec 5, 2008 at 2:36 AM, Xiaofan Chen <[hidden email]> wrote:
>
>> On Fri, Dec 5, 2008 at 2:31 PM, solarwind <[hidden email]>
>> wrote:
>> > Hey all,
>> >
>> > I'm trying to build a scientific RPN calculator using a PIC
>> microcontroller.
>> > It will be battery powered and for use in school. I'll be using it with
>> an
>> > HD44780 based LCD character display and my own keypad.
>> >
>> > I was then tempted by the PIC32 series. These chips look perfect for my
>> > project. I'm now only concerned about the power usage of these things.
>> Does
>> > anyone know the power usage for the PIC32 series?
>> >
>> > Anyway, I need advice. Which series of microcontroller should I chose
>> for my
>> > project?
>>
>> http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=71281
>> So you have already did some study.
>>
>> You can go to Microchip PIC32 website to do more research.
>> http://www.microchip.com/pic32
>>
>>
>> Xiaofan
>> --
>> http://www.piclist.com PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>>
>
>
>
> --
> ..::[ solarwind ]::..
>



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Re: Which PIC? 16F, 18F or 32?

Randy Glenn-2
Page 597 of the PIC32MX3XX/4XX datasheet shows the operating current:

http://ww1.microchip.com/downloads/en/DeviceDoc/61143E.pdf

That doesn't tell you the whole story though, as is outlined in the
notes on that page.

-Randy

On Fri, Dec 5, 2008 at 3:17 AM, solarwind <[hidden email]> wrote:

> I'm also asking in a lot of different places to get different opinions. I
> don't want to make mistakes. The good people at the AVR forum showed me
> roughly how much space I'll be needing, not including my own functions and
> RPN logic and possible graphing features. The main concern now is the power
> usage. So how much power does the PIC32 use?
>
> On Fri, Dec 5, 2008 at 3:15 AM, solarwind <[hidden email]> wrote:
>
>> Already looked on the PIC32 site, couldn't find the power usage of the
>> PIC32.
>>
>>
>> On Fri, Dec 5, 2008 at 2:36 AM, Xiaofan Chen <[hidden email]> wrote:
>>
>>> On Fri, Dec 5, 2008 at 2:31 PM, solarwind <[hidden email]>
>>> wrote:
>>> > Hey all,
>>> >
>>> > I'm trying to build a scientific RPN calculator using a PIC
>>> microcontroller.
>>> > It will be battery powered and for use in school. I'll be using it with
>>> an
>>> > HD44780 based LCD character display and my own keypad.
>>> >
>>> > I was then tempted by the PIC32 series. These chips look perfect for my
>>> > project. I'm now only concerned about the power usage of these things.
>>> Does
>>> > anyone know the power usage for the PIC32 series?
>>> >
>>> > Anyway, I need advice. Which series of microcontroller should I chose
>>> for my
>>> > project?
>>>
>>> http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=71281
>>> So you have already did some study.
>>>
>>> You can go to Microchip PIC32 website to do more research.
>>> http://www.microchip.com/pic32
>>>
>>>
>>> Xiaofan
>>> --
>>> http://www.piclist.com PIC/SX FAQ & list archive
>>> View/change your membership options at
>>> http://mailman.mit.edu/mailman/listinfo/piclist
>>>
>>
>>
>>
>> --
>> ..::[ solarwind ]::..
>>
>
>
>
> --
> ..::[ solarwind ]::..
> --
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Re: Which PIC? 16F, 18F or 32?

Danny Miller-2
In reply to this post by V G
How many features?  How fast?
A 16F could implement the basic functions.  I assume there are floating
point routines for the 16F available for download somewhere.

18F does have the C compiler and all... it's not a bad idea.  There
aren't many 16F compilers because they're not very good- because the 16F
series lacks some features which makes them difficult to compile for
efficiently.

How much battery voltage do you have, and how many batts?  The HD44780
display alone will probably take a bit much for button batteries.  But
the question is also voltage.  A 5v display needs 4 alkaline batts
unless you use a boost regulator.

One thing to understand is you won't be able to compete with a regular
calc for power consumption.  Those things have the integrated LCD drive
and all and you will be taking 10x-100x more power with the best of designs.

dsPIC30F takes a LOT of power.
dsPIC33F takes a lot less, runs on 3.3v, but it's still probably too
much.  And IIRC they have really bad Sleep current relative to say 18F,
and that will hurt you a lot.

There's also the Microchip C18 compiler.  Personally, I have a big
project that ran much slower on Microchip's C18 than it did with HiTech
PICC18.  But I suspect that was a conflict with my coding style
somewhere, I don't know, I did have the optimizations working and all.  
C18 is supposed to be as fast or faster performance, I've used it a lot
but have never compared the two other than that initial project.  I'd
recommend C18 over PICC18, just don't see a compelling reason to go
third-party.

Danny

solarwind wrote:

> Hey all,
>
> I'm trying to build a scientific RPN calculator using a PIC microcontroller.
> It will be battery powered and for use in school. I'll be using it with an
> HD44780 based LCD character display and my own keypad.
>
> Basically, I'll need enough flash and RAM on the PIC to store all the
> functions a scientific calculator would have (sin, cos, tan, asin, acos,
> atan, log, ln, ee, e^x, pow, sqrt and so on). As for the second requirement,
> I'll need it to be as low power as possible as it will run on small
> batteries.
>
> Also, I'll be programming in C using HI-TECH's highly optimizing C compiler
> for the PIC. This compiler is amazing.
>
> I've already looked at the PIC 16F series. These seem to use low power but
> I'm scared that they will not have enough flash (and possibly RAM) for my
> application.
> Then I looked at the 18F series. These also seem to be low power and have a
> lot more RAM and flash.
> I was then tempted by the PIC32 series. These chips look perfect for my
> project. I'm now only concerned about the power usage of these things. Does
> anyone know the power usage for the PIC32 series?
>
> Anyway, I need advice. Which series of microcontroller should I chose for my
> project?
>
>  

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Re: Which PIC? 16F, 18F or 32?

Alan Pearce - UKRI STFC
In reply to this post by Randy Glenn-2
Not sure that you would need to go to a PIC32 for your calculator
application. A Pic 24 would be adequate I suspect.

Also to bootstrap yourself up you could look at the Explorer16 schematics
and software. The Explorer16 has exactly the type of display you are looking
at, fitted to it, and the demonstration software for the PIC24 PIM modules
has the LCD software available.

Another loop to look at is the book "Programming 16-bit Microcontrollers in
C - Learning to Fly the PIC24" which is referenced from the Microchip PIC24
pages. The writer of that also does an LCD and PC Keyboard interface. The
authors website also has updated software on it, from that supplied on the
CD that comes with the book.

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Re: Which PIC? 16F, 18F or 32?

Gerhard Fiedler-3
In reply to this post by Danny Miller-2
On 2008-12-05 07:02:35, Danny Miller wrote:

> Personally, I have a big project that ran much slower on Microchip's C18
> than it did with HiTech PICC18.  [...] I'd recommend C18 over PICC18,
> just don't see a compelling reason to go third-party.

??? :)

Gerhard
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Re: Which PIC? 16F, 18F or 32?

Olin Lathrop
In reply to this post by V G
solarwind wrote:
> I'm trying to build a scientific RPN calculator using a PIC
> microcontroller. It will be battery powered and for use in school.

If you just want to use it, then this is silly.  Get a HP 33S, which I think
is the only RPN scientific calculator they still make.

Unless you're doing this for the experience, this is a waste of time that
will result in something much more klunky and less usable than the 33s,
which can be had for under $50 if I remember right.


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(978) 742-9014.  Gold level PIC consultants since 2000.
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Re: Which PIC? 16F, 18F or 32?

Olin Lathrop
In reply to this post by Danny Miller-2
Danny Miller wrote:
> A 16F could implement the basic functions.

Then you need take another look at all the things a real scientific
calculator does.  There are many trancendental functions that will require
large code, even with the assist of lookup tables.  Either way, a lot of
program memory is required.  Even with a large external ROM to store lookup
tables, I seriously doubt you could implement all the features of a real
scientific calculator in 8K instruction words.

> I assume there are floating
> point routines for the 16F available for download somewhere.

I don't, at least not the type required for implementing a calculator.
Calculators usually do their math in wide decimal, something like 14 digits.
Even if doing it in binary, you want at least 48 bits to meet "scientific
calculator" level specs.  Maybe someone has developed floating point
routines with 48 bit mantissas, but most likely not.

Real microcontroller applications rarely need more than 16 bits mantissa.  I
have floating point routines that run on a PIC 16, but they use 24 bits, 16
for the mantissa, 7 for the exponent, and 1 sign bit.  That's all that was
needed in the 100 or so PIC applications I've done so far.


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Re: Which PIC? 16F, 18F or 32?

Thomas C Sefranek
In reply to this post by Olin Lathrop
Bahhh!

HP makes and sells at least 4 calculators with RPN option.
http://h10010.www1.hp.com/wwpc/us/en/sm/WF04a/215348-215348-64232-20037-215351.html
  *
  |  __O    Thomas C. Sefranek  [hidden email]
  |_-\<,_   Amateur Radio Operator: WA1RHP
  (*)/ (*)  Bicycle mobile on 145.41, 448.625 MHz

ARRL Instructor, Technical Specialist, VE Contact.
http://hamradio.cmcorp.com/inventory/Inventory.html
http://www.harvardrepeater.org
----- Original Message -----
From: "Olin Lathrop" <[hidden email]>
To: "Microcontroller discussion list - Public." <[hidden email]>
Sent: Friday, December 05, 2008 7:06 AM
Subject: Re: [PIC] Which PIC? 16F, 18F or 32?


> solarwind wrote:
>> I'm trying to build a scientific RPN calculator using a PIC
>> microcontroller. It will be battery powered and for use in school.
>
> If you just want to use it, then this is silly.  Get a HP 33S, which I
> think
> is the only RPN scientific calculator they still make.
>
> Unless you're doing this for the experience, this is a waste of time that
> will result in something much more klunky and less usable than the 33s,
> which can be had for under $50 if I remember right.
>
>
> ********************************************************************
> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> (978) 742-9014.  Gold level PIC consultants since 2000.
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist


--------------------------------------------------------------------------------



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Checked by AVG - http://www.avg.com
Version: 8.0.176 / Virus Database: 270.9.14/1831 - Release Date: 12/4/2008
9:55 PM

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Re: Which PIC? 16F, 18F or 32?

Tamas Rudnai
One should make an RPN calc with a Forth extention :-) Anyway, those HP
calculators are awesome!

Tamas



On Fri, Dec 5, 2008 at 12:55 PM, Thomas C Sefranek <[hidden email]> wrote:

> Bahhh!
>
> HP makes and sells at least 4 calculators with RPN option.
>
> http://h10010.www1.hp.com/wwpc/us/en/sm/WF04a/215348-215348-64232-20037-215351.html
>  *
>  |  __O    Thomas C. Sefranek  [hidden email]
>  |_-\<,_   Amateur Radio Operator: WA1RHP
>  (*)/ (*)  Bicycle mobile on 145.41, 448.625 MHz
>
> ARRL Instructor, Technical Specialist, VE Contact.
> http://hamradio.cmcorp.com/inventory/Inventory.html
> http://www.harvardrepeater.org
> ----- Original Message -----
> From: "Olin Lathrop" <[hidden email]>
> To: "Microcontroller discussion list - Public." <[hidden email]>
> Sent: Friday, December 05, 2008 7:06 AM
> Subject: Re: [PIC] Which PIC? 16F, 18F or 32?
>
>
> > solarwind wrote:
> >> I'm trying to build a scientific RPN calculator using a PIC
> >> microcontroller. It will be battery powered and for use in school.
> >
> > If you just want to use it, then this is silly.  Get a HP 33S, which I
> > think
> > is the only RPN scientific calculator they still make.
> >
> > Unless you're doing this for the experience, this is a waste of time that
> > will result in something much more klunky and less usable than the 33s,
> > which can be had for under $50 if I remember right.
> >
> >
> > ********************************************************************
> > Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> > (978) 742-9014.  Gold level PIC consultants since 2000.
> > --
> > http://www.piclist.com PIC/SX FAQ & list archive
> > View/change your membership options at
> > http://mailman.mit.edu/mailman/listinfo/piclist
>
>
>
> --------------------------------------------------------------------------------
>
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com
> Version: 8.0.176 / Virus Database: 270.9.14/1831 - Release Date: 12/4/2008
> 9:55 PM
>
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Re: Which PIC? 16F, 18F or 32?

Mongol Herdsman
In reply to this post by V G
solarwind wrote:
> I'm also asking in a lot of different places to get different opinions. I
> don't want to make mistakes. The good people at the AVR forum showed me
> roughly how much space I'll be needing, not including my own functions and
> RPN logic and possible graphing features. The main concern now is the power
> usage. So how much power does the PIC32 use?

Time you've spent asking good people, possibly would be better spent
on programming you IPhone, HTC Touch or whatever SmartPhone/PDA you
owe.

Regards.
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Re: Which PIC? 16F, 18F or 32?

M. Adam Davis-2
In reply to this post by V G
On Fri, Dec 5, 2008 at 1:31 AM, solarwind <[hidden email]> wrote:
> Hey all,
>
> I'm trying to build a scientific RPN calculator using a PIC microcontroller.
> It will be battery powered and for use in school. I'll be using it with an
> HD44780 based LCD character display and my own keypad.

Actually, why don't you just build or buy one of these:

http://www.calcwatch.com/index.html

It's an open source (software, schematic) PIC24 based scientific RPN
calculator in a watch form factor.

So you can build one yourself, and then modify the source code as
needed for your own purposes.  When he has them in stock, they're only
$100, which is far less than what you'll spend building your own.

>From the site:
----------
The uWatch is an RPN and Algebraic scientific calculator watch that
you can build yourself.
The software is OPEN SOURCE under the GPL license.

Specifications:

    *      Processor - 16 bit Microchip PIC24FJ64GA004
    *      Program memory - 64KB of Flash
    *      SRAM - 8KB
    *      Available user EEPROM memory - 64KB
    *      Calculator modes - 4 Level HP style RPN stack, or Casio
(pre-VPAM) style Algebraic with 6 level of parentheses
    *      Precision - 64bit IEEE floating point. 9 digit display + exponent
    *      Programming - Macro style keystroke programming mode. 60 x
1024 steps.
    *      Time and date display. Selectable 12/24hr format
    *      Clock Speed - 250KHz normal operation, 32.768KHz sleep
mode. 8MHz maximum speed.
    *      Display - 16 character x 2 line dot matrix
    *      Sleep mode - LCD switches of after timeout to increase
battery life. Picks up where it left off.
    *      Backlight - Yellow LED (quite dim)
    *      Battery - single or dual lithium CR2032
    *      Battery life - 100hrs+ operation. 1 year+ in sleep mode.
    *      Size - 54mm x 43mm x 20mm(at the thickest point)
    *      Watch band - any standard 20-22mm watch band. Standard 22mm
watch spring bars.
    *      Programming Interface - Microchip ICSP. Compatible with
MPLAB ICD2 or compatible programmer.
    *      Serial port - UART based universal serial port. RS232 and
IrDA compatible with optional interface circuits.
    *      Language - All source code written with the free MPLAB C30 compiler
----------

-Adam

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Re: Which PIC? 16F, 18F or 32?

V G
Thank you Randy Glenn and Danny Miller. I don't want to go with a 16 bit
chip. HI-TECH's compilers are really good. I stuck a lot of scientific
functions using the PICC compiler for PIC 16 in less than 7K code myself
using their compiler. Floating point.

If I wanted to buy one, I wouldn't have consulted you guys.

>Mongol Herdsman:
>Time you've spent asking good people, possibly would be better spent
>on programming you IPhone, HTC Touch or whatever SmartPhone/PDA you
>owe.

>Regards.

With attitude like that, you're probably right, except I don't own any such
device.

And I'm also well aware of the calc watch and HP's RPN calculators (I own a
41CV). I just want to build one. I'm asking for help from you guys, not your
permission or discouragement.

Thanks again Randy Glenn and Danny Miller for your posts.

On Fri, Dec 5, 2008 at 12:33 PM, M. Adam Davis <[hidden email]> wrote:

> On Fri, Dec 5, 2008 at 1:31 AM, solarwind <[hidden email]> wrote:
> > Hey all,
> >
> > I'm trying to build a scientific RPN calculator using a PIC
> microcontroller.
> > It will be battery powered and for use in school. I'll be using it with
> an
> > HD44780 based LCD character display and my own keypad.
>
> Actually, why don't you just build or buy one of these:
>
> http://www.calcwatch.com/index.html
>
> It's an open source (software, schematic) PIC24 based scientific RPN
> calculator in a watch form factor.
>
> So you can build one yourself, and then modify the source code as
> needed for your own purposes.  When he has them in stock, they're only
> $100, which is far less than what you'll spend building your own.
>
> >From the site:
> ----------
> The uWatch is an RPN and Algebraic scientific calculator watch that
> you can build yourself.
> The software is OPEN SOURCE under the GPL license.
>
> Specifications:
>
>    *      Processor - 16 bit Microchip PIC24FJ64GA004
>    *      Program memory - 64KB of Flash
>    *      SRAM - 8KB
>    *      Available user EEPROM memory - 64KB
>    *      Calculator modes - 4 Level HP style RPN stack, or Casio
> (pre-VPAM) style Algebraic with 6 level of parentheses
>    *      Precision - 64bit IEEE floating point. 9 digit display + exponent
>    *      Programming - Macro style keystroke programming mode. 60 x
> 1024 steps.
>    *      Time and date display. Selectable 12/24hr format
>    *      Clock Speed - 250KHz normal operation, 32.768KHz sleep
> mode. 8MHz maximum speed.
>    *      Display - 16 character x 2 line dot matrix
>    *      Sleep mode - LCD switches of after timeout to increase
> battery life. Picks up where it left off.
>    *      Backlight - Yellow LED (quite dim)
>    *      Battery - single or dual lithium CR2032
>    *      Battery life - 100hrs+ operation. 1 year+ in sleep mode.
>    *      Size - 54mm x 43mm x 20mm(at the thickest point)
>    *      Watch band - any standard 20-22mm watch band. Standard 22mm
> watch spring bars.
>    *      Programming Interface - Microchip ICSP. Compatible with
> MPLAB ICD2 or compatible programmer.
>    *      Serial port - UART based universal serial port. RS232 and
> IrDA compatible with optional interface circuits.
>    *      Language - All source code written with the free MPLAB C30
> compiler
> ----------
>
> -Adam
>
> --
> Please rate and vote for my contest entry:
> http://mypic32.com/web/guest/profiles?profileID=50331
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>



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Re: Which PIC? 16F, 18F or 32?

V G
In reply to this post by Olin Lathrop
Whoever said just 8K? My pic18 has 64K. That good enough sir?

On Fri, Dec 5, 2008 at 7:19 AM, Olin Lathrop <[hidden email]>wrote:

> Danny Miller wrote:
> > A 16F could implement the basic functions.
>
> Then you need take another look at all the things a real scientific
> calculator does.  There are many trancendental functions that will require
> large code, even with the assist of lookup tables.  Either way, a lot of
> program memory is required.  Even with a large external ROM to store lookup
> tables, I seriously doubt you could implement all the features of a real
> scientific calculator in 8K instruction words.
>
> > I assume there are floating
> > point routines for the 16F available for download somewhere.
>
> I don't, at least not the type required for implementing a calculator.
> Calculators usually do their math in wide decimal, something like 14
> digits.
> Even if doing it in binary, you want at least 48 bits to meet "scientific
> calculator" level specs.  Maybe someone has developed floating point
> routines with 48 bit mantissas, but most likely not.
>
> Real microcontroller applications rarely need more than 16 bits mantissa.
>  I
> have floating point routines that run on a PIC 16, but they use 24 bits, 16
> for the mantissa, 7 for the exponent, and 1 sign bit.  That's all that was
> needed in the 100 or so PIC applications I've done so far.
>
>
> ********************************************************************
> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> (978) 742-9014.  Gold level PIC consultants since 2000.
> --
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> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>



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Re: Which PIC? 16F, 18F or 32?

V G
In reply to this post by Olin Lathrop
How much you wanna bet it'll be more clunky and less usable? I've written
most of the code, made the keypad, assembled the LCD, mounted it onto the
case. All that's left to do is make my decision about the microcontroller
and mount it.

On Fri, Dec 5, 2008 at 7:06 AM, Olin Lathrop <[hidden email]>wrote:

> solarwind wrote:
> > I'm trying to build a scientific RPN calculator using a PIC
> > microcontroller. It will be battery powered and for use in school.
>
> If you just want to use it, then this is silly.  Get a HP 33S, which I
> think
> is the only RPN scientific calculator they still make.
>
> Unless you're doing this for the experience, this is a waste of time that
> will result in something much more klunky and less usable than the 33s,
> which can be had for under $50 if I remember right.
>
>
> ********************************************************************
> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> (978) 742-9014.  Gold level PIC consultants since 2000.
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>



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Re: Which PIC? 16F, 18F or 32?

V G
Bingo! I would do something like this:

"The LPRC oscillator is separate from the FRC. It oscil-
lates at a nominal frequency of 31.25 kHz. The LPRC
oscillator is the clock source for the Power-up Timer
(PWRT), Watchdog Timer (WDT), Fail Safe Clock Mon-
itor (FSCM) and PLL reference circuits. It may also be
used to provide a low-frequency clock source option for
the device in those applications where power
consumption is critical, and timing accuracy is not
required."

Then do something like this:

http://pastebin.com/f4ee1f4fc



On Fri, Dec 5, 2008 at 2:19 PM, solarwind <[hidden email]> wrote:

> How much you wanna bet it'll be more clunky and less usable? I've written
> most of the code, made the keypad, assembled the LCD, mounted it onto the
> case. All that's left to do is make my decision about the microcontroller
> and mount it.
>
>
> On Fri, Dec 5, 2008 at 7:06 AM, Olin Lathrop <[hidden email]>wrote:
>
>> solarwind wrote:
>> > I'm trying to build a scientific RPN calculator using a PIC
>> > microcontroller. It will be battery powered and for use in school.
>>
>> If you just want to use it, then this is silly.  Get a HP 33S, which I
>> think
>> is the only RPN scientific calculator they still make.
>>
>> Unless you're doing this for the experience, this is a waste of time that
>> will result in something much more klunky and less usable than the 33s,
>> which can be had for under $50 if I remember right.
>>
>>
>> ********************************************************************
>> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
>> (978) 742-9014.  Gold level PIC consultants since 2000.
>> --
>> http://www.piclist.com PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>>
>
>
>
> --
> ..::[ solarwind ]::..
>



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Re: Which PIC? 16F, 18F or 32?

Olin Lathrop
In reply to this post by V G
solarwind wrote:
> With attitude like that, you're probably right, except I don't own
> any such device.
>
> And I'm also well aware of the calc watch and HP's RPN calculators (I
> own a 41CV). I just want to build one. I'm asking for help from you
> guys, not your permission or discouragement.

With attitude like that you're going to piss people off that you are seeking
a favor from.  If people think you're doing something silly, they can and
probably will say so.  Get over it.  Sometimes we get people here who really
don't know better when they ask for something silly.

You could have saved yourself those type of responses if you had been more
clear in the first place.  You originally said it would be "for use in
school".  In other words, you want to *use* the calculator, as apposed to
building it for a assignment or because you want the experience.  Given that
as the purpose, "go buy one" is absolutely the correct answer.  If you had
stated the purpose correctly, you would have gotten rather different
answers.  People responded to your post correctly.  It was you who screwed
up, so grow up and stop whining about the answers you got as a result.


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(978) 742-9014.  Gold level PIC consultants since 2000.
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Re: Which PIC? 16F, 18F or 32?

Wouter van Ooijen
In reply to this post by V G
solarwind wrote:
> Whoever said just 8K? My pic18 has 64K. That good enough sir?

Certainly enough, but also totally irrelevant, because it was a reponse to

 >>> A 16F could implement the basic functions.

--

Wouter van Ooijen

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