[sdiy] PIC 16F1788 CPU bug

[Scott Gravenhorst]

Tom Wiltshire <tom at electricdruid.net> wrote:
>
>On 29 Nov 2013, at 16:10, Andre Majorel <aym-htnys at teaser.fr> wrote:
>
>> Seeing as most of us deal with small runs or prototypes, that
>> would make AVR the logical choice. And yet PIC projects seem to
>> outnumber AVR projects.
>> 
>> Am I missing something ?
>
>No, I don't think so. You're maybe overestimating the amount of 
>logic that goes into these decisions. 
>
>Having spent several years playing with this stuff, I reckon I 
>could now make a logical and informed choice about which is the 
>better platform for a given task. However, at the point I was 
>trying to decide which platform to opt for, I knew virtually 
>nothing about it and it was mostly dumb luck. The careful choice 
>of the 16F684 processor for all my early projects was entirely 
>the result of the fact that that's what I had available with my 
>first PICKit 1 programmer! 
>
>We think that these choices are worked out, but mostly they're 
>not. You only find out later if you made the right choice or not, 
>and by then it's too late. Luckily, in the case of processors, I 
>don't think it matters hugely, and certainly not at our level. 
>You can make any of them do any of the stuff that we might want 
>them to do, although some will do some bits more easily and 
>others other bits more easily. 

I find myself in a mea culpa.  I know perfectly well that Microchip has published
errata before I even buy their IC.  Yet, for some reason (too much in a damn
hurry), I do not.  What this has taught me in theory is that it's a good idea to
spend time planning the project as completely as possible.  This will then flush
out what peripherals and features are required of the given project CPU.  If I
were to read the errata after the planning, I might know before hand 1) if there
is an issue with a peripheral or feature I need and 2) if there is a good
workaround.  In this workflow, I might decide not to buy that particular IC if
those required features are critical.  

Of course, I could have said that this way: hindsight is 20/20.

Fortunately for me in my CPU meanderings, I've not had errata effect my projects.
 Some very near misses tho.

BTW, I'm finding the dsPIC33F quite a nice/powerful device.  Current project is a
single dsPIC33F128 (at 40 MIPS) running a 6 voice Karplus-Strong MIDI synth which
has pitch bend and pitch warp features.  The synth supports a 5 octave range and
uses analog pots (or external CVs) to control it's timbre.  Timbre is a continuum
from somewhat steel like string sounds through nylon harp-ish sounds through
resonant drums.

Yes, I've read the errata by now.    (c:

-- ScottG
________________________________________________________________________
-- Scott Gravenhorst
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