[sdiy] dspic VCDO

[Tom Wiltshire]

On 17 Aug 2008, at 13:07, Csaba Zvekan wrote:

> Ryan,
>
> I think life expectancy and performance may also be an issue. Of  
> course you can over clock your MCU and at first every thing seems  
> to work fine . But the problem arises over time when the part is in  
> stress for a longer period. Overheating is the main cause of all  
> our electronic problems. And this can cause timing instabilities as  
> well.
> But my question is : could you run your design at  µC 8XPLL @10MHz  
> running at 80MHz ? Or would some parts of the routines be too slow ?

If he's not got much free time in the code, shaving a third off the  
code's runtime is pretty difficult.

I've often been back through bits of dsPIC assembly code I've written  
to try and optimise it some more. Occasionally you get lucky and spot  
a better way to do something you did inefficiently at first, but  
mostly it only amounts to a few tweaks here and there - perhaps 5%,  
but not much more than that.

I looked at his code and didn't see anything that struck me as hugely  
inefficient. Quite the reverse, in fact.

T.