Re: dsPIC33F Lua support (Was: Advocating Lua on an embedded systems fair)

[Olivier Galibert <galibert@...>]

On Wed, Feb 11, 2009 at 11:21:10AM +0000, David Given wrote:
> Of course, given that the low end PICs run at 4MHz or so and that
> emulation overhead is *at least* an order of magnitude, you're probably
> going to end up with a device roughly equivalent to a 500kHz real
> processor. Even Lua might have trouble running at an acceptable speed on
> that.

My emulation experience (I'm a Mame developper) makes me think it will
be 50Khz at best rather than 500.  A 8-bit system won't have the
registers to keep the emulated cpu registers live and will not have
the ALUs to do the 32-32 arithmetic ops efficiently, including all the
add/sub/shift you need to do for effective address computation.

  OG.