Brendan Moran <PICLIST@mitvma.mit.edu> wrote:

> I'm not arguing about convention, here.

    Brendan:

    I admire your independent thinking; it's nice to see someone
    discarding the usual assumptions and starting over from
    more-or-less basic principles.

    It's useful to keep in mind, though, that when you see a design
    feature common to nearly all microcontrollers, it probably exists
    for reasons other than arbitrary "convention".

> I hope you can see that there are other functional schemes that
> could use a full RAM clear in the reset process.  I don't think
> there'd be much loss there, but there might be very little gain.
> I'll leave that analysis to the professional chip designers.

    As a professional chip designer, I agree that a full RAM clear
    IS generally needed on reset.  However, I don't think it should
    automatically be performed by the hardware.

    I mean, even the 18F's RAM can be cleared in fewer than 12
    software instructions.  Even if the micro cleared all RAM
    automatically on reset, that 12-instruction routine would
    probably be in most programs anyway, in order to clear RAM when
    necessary under other circumstances (e.g., WDT reset).

    -Andy

=== Andrew Warren -- aiw@cypress.com
=== Principal Design Engineer
=== Cypress Semiconductor Corporation
===
=== Opinions expressed above do not
=== necessarily represent those of
=== Cypress Semiconductor Corporation

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