Re: PIC versus AVR

On 2006-08-04, Ulf Samuelsson <ulf@xxxxxxxxxxxxx> wrote:

Any processor that falls over when you attempt to do any
pointer manipulation isn't C-friendly.

You are probably saying that an 8 bit architecture is
inherently C-unfriendly.

After thinking more about the question, yes, an 8-bit
architecture is inherently more C-unfriendly than one which
supports "pointer-length" operations.

If you start in the other end: How do you make an 8 bit
architecture which is C-friendly you may come to a different
conclusion.

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.

From this viewpoint it is "C-friendly" to use 2 instructions
for 16 bit operations and 4 instructions to do 32 bit
operations.

Not as C-friendly as using 1. :)

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Relevant Pages

  • Re: Microchip Introduces First 16-bit Microcontroller Product Line - the PIC24
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  • Re: Moving from 8051 to AVR
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  • Re: Moving from 8051 to AVR
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