Re: PIC versus AVR


"steve" <bungalow_steve@xxxxxxxxx> skrev i meddelandet
news:1154925894.357276.223680@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Grant Edwards wrote:

Start at yet another end again: why pick an 8-bit architecture
if you're using a language or writing an application that needs
to do a lot of 16-bit operations? Something like an MSP430
(16-bit) or H8 (16/32 bit) is cheaper than an AVR, and makes
life easier. I particularly like the H8/300 which provides
atomic read/write of 32-bit variables (long integers and
floats): that eliminates the requirements for a lot of mutexes.

Well the H8/300's max out at 2K RAM (8K for AVR's) 60K FLASH (256K
AVR's), requires 50% more power, are physically bigger, have no
EEPROM, limited selection, there is a price to pay in die size when you
move up to a 16 bit processor which can make your life harder it other
aspects, I also seem to remember doing a H8/300 16 bit multiply was
slower then a AVR's 16 bit multiply and generally slower in all
instructions, so it's not so cut and dry as you imply if you dig into
the details. The MSP430's are not cheaper then the AVR's.


In the end, I think C friendly means that you rather use a C compiler
than assembler to get the job done on the MCU, even for cost critical
designs.

I find regularily that when I get my hands on customers assembly code to fix
problems,
I can do a better job with the C compiler.

--
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB


.

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