What microcontroller should I buy?

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View


With so many different types of microcontrollers and manufacturers on
the market, it is rather difficult to know where to begin.

What I need is something that has the following features:

* very small in size
* very low power consumption
* at least 64 k of storage purely for storing data (this is in addition
to my program's space)
* some sort of interface to connect the microcontroller to a PC (RS232,
USB, etc) to allow the microcontroller app to transfer logged data.
* an interface to communicate with a serial peripheral (RS232 would
probably do)
* low cost or free Integrated Development Environment (IDE) with
debugging capabilities
* low cost or free C or Basic compiler (or some other high level
language)
* low cost hardware kit for flashing the microcontroller and debugging

The applications running on the microcontroller will generally be
small. Also, if it isn't possible to have at least 64 k of built-in
memory, I can live with adding the memory externally but the
enhancement should be easy to do.

Can anyone please make any suggestions on any products / manufacturers
that have what I am looking for.

Thank you
Johann Blake


Re: What microcontroller should I buy?


Quoted text here. Click to load it

A good place to start is
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId74%
where you can select PICs based on your options.  Combining your
requirement for low pin count and 64K memory gives 3 28 pin PICs with
64K (18F26xx).  Microchip also offer the MPLAB IDE as a free download.

You could either prototype your design on a standard breadboard and use
discrete components to build the interface to the PC  to communicate
with your application on the PC, or use a development system like these

http://www.breadboarding.co.uk/Merchant2/4.13/merchant.mv?Screen=PROD&Store_Code=1&Product_CodeEA%SYPIC2
http://www.mikroelektronika.co.yu/english/product/tools/easypic3.htm

MikroBASIC also offer their own high level language and compiler.  The
freeware version is limited to 2K which is ample for most applications.
More details
http://www.mikroelektronika.co.yu/english/product/compilers/mikrobasic /

For programming the HEX to the PIC you could either build you own
programmer or purchase one from as little as $12 from Spark Fun
http://www.sparkfun.com/shop/index.php?shop=1&cart50%2678&cat=3&
although some of the development systems above also include the
programmer, so its really down to your budget and personal preference.

Other languages you might want to look at are;
JAL & JalEDIT - (JalEDIT is a freeware IDE for use with JAL)
PicBASIC (pro)
CH BASIC
MBASIC

Just goggle or Yahoo for the above.

That should be enough for you to be getting on with :-)

Malcolm

Re: What microcontroller should I buy?



Quoted text here. Click to load it

You will probably need to add an external 64k EEPROM or similar to get what
you want easilly AND cheaply (in fact if you plan to log lots then perhaps a
RAMTRON device would be better). If that's the case then any micro will
probably do(depends of course what you want to do with it). I guess you'll
be driven by the cost of the tools. So... There's always free C compilers
somewhere (see a short list below), usually with some limitations [code size
etc.] and therefore the debugger might be your stumbling block... but then
again processors with on-chip debug facilities are usually good for low cost
debuggers.

There are several very low cost debuggers for Microchip PICs (quick search
on web will list lots) Many are less than $99.
Reasonably low cost for HCS08
etc.
As far as 'flashing' the micro... your debugger can probably do that for
you.

Compilers
Microchip PIC18 = free C18 compiler download from Microchip (not code size
limited but code optimisation limited) along with MPLAB IDE
ST ST7 = free 16K version of the Cosmic compiler and use STs visualIDE &
debug system
Motorolla HCS08 = Metrowerks 4k limited compiler (Version 5 available Jan
2006 will be 8k or 16k I believe)
Renesas  have a 64k limited (if you call that limited) C compiler...
and so on...

The web is great for finding these tools.

This info probably hasn't helped you choose your micro family. It's all very
subjective and I wouldn't want to influence you by just mentioning my
favourite.
Good luck
Jim









Re: What microcontroller should I buy?



[snip...snip...]
Quoted text here. Click to load it

Serial EEPROMs are (relatively) cheap and simple to interface. They also
have the benefit of being non-volatile but at the price of being a bit
slower than a "main memory" SRAM space. Search Digikey for "serial
eeprom" and take your pick. (no pun intended ...)

You could also go with an MMC card for removable storage.
www.avrfreaks.com has pointers to a low cost commercial FAT file system
for MMC cards or, if you just need flat storage space, the MMC interface
spec is available on the net.

Quoted text here. Click to load it

Lots and lots of microcontrollers come with integrated UARTs. Generally
you'll need to add the level shifter, commonly a MAX232A or equivalent.

Quoted text here. Click to load it

The WinAVR project is linked off the AVRFreaks site above. Personally I
use the Imagecraft AVR C compiler; not free but reasonably priced and a
good product.

Quoted text here. Click to load it

Atmel's "AVR Studio" works with the Imagecraft compiler as a source-
level debugging environment. You can get the AVRISP in-system programmer
for about $30.

--
Rich Webb   Norfolk, VA

Re: What microcontroller should I buy?


Try www.technologicalarts.ca or type in technological arts on google. I
would recommend 9s12 microcontroller. It is compact, cheap and efficient.
They have Adapt9s12 where you can connect to your PC to program and debug.
If you order one from them you can also get the compiler for free. Plus they
can help you if you have questions, they also have toll free number on their
website.

Later, Wojtek



Quoted text here. Click to load it



Re: What microcontroller should I buy?


Quoted text here. Click to load it
Any micro controller that supports external memory will serve your needs
provided you interface the required external memory.  I prefer the
megaAVR family over the PIC's because they are well supported by the "C"
language using the 'free' GNU compilier.  The fact that there is a low
cost JTAG ICE available for debugging is icing on the cake.

If you outgrow the AVR family there are several variants of the ARM
processor family that can directly address as much as 1 megabyte (or more?)
of memory.

BTW the AVR is a Harvard class machine, the ARM's are Von-Neuman (if
that matters).

Re: What microcontroller should I buy?


Quoted text here. Click to load it

How does the JTAG ICE work in a Linux environment?  I recently started
playing with the stk500 and atmega8515 in linux.  I have avrdude and
avr-gcc working flawlessly but am wondering about any issues that might
surround using the JTAG via USB  in linux.

BTW: seems that the AVR family has a better mips:hz ratio than PIC too.



Site Timeline