At 18.12 2012.02.08, you wrote:
>Thank you both, Mario and Alan.
>
>I checked errata for 30f4011 and discovered it has "lots" of "bugs", my
>next micro will be a 33F or 33EP (I love 33EP256MU806 specs for a 64 pin
>micro).
>
>It is not possible to do AD conversions at 1 Msps due to bugs, max is 750
>ksps.
>
>After inspection of assembly output from my C compiler, I discovered it wa=
s
>setting SAMC and ADCS in ADCON3 register at its maximum values (SAMC=3D111=
11
>"31 Tad" and ADCS=3D111111 "32 Tcy"). That was the reason of its slow spee=
d.
>Now, lowering this values I speeded it up a lot. I have to check for
>integrity of data at that speed, but looks promissing and more acceptable.
>
>I still have a lot of doubts, but the increase of speed makes me happy and
>do not need to dig more into the question by the moment.
>
>Thanks again.

You're welcome.

I just stumbled upon another problem, but on a PIC32MX1XX: when I enabled
compiler optimizations, the ADC results looked buggy. In the end, as I am
using autosampling, I had to put at least a NOP or a DONE=3D0 between the l=
ine
with SAMP=3D1 and the loop where I check if DONE became 1. I found the "bug=
"
as I had suspected in the past that this would be necessary, however the
documentation didn't specify it was, so I omitted the extra code. Now I
know it was due.. it happens very rarely that the loop get skipped as it
finds DONE at 1 because of the previous conversion and SAMP=3D1 didn't clea=
r
it in time (however I am now going to disassemble it do see if it's the
compiler that maybe reordered the instructions!), but as it was for a buck
SMPS converter loop, it caused some visible (smoky) problems. :D

Cheers,
Mario

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