On 2/19/2013 11:00 AM, Manu Abraham wrote:
> Hi,
>
> I have a dsPIC33FJ16GS502 with a 10MHz xtal as the Primary Oscillator,
> connected between OSC1 and OSC2 along with 2x15pf caps.
>
> While expecting the device to run at 40MIPS, all I see is that RA3
> toggles around 3.3Mhz and 5MHz as can be seen.
>
> RA3 is connected to a LED and Channel 1 of a Logic Sniffer..
>
> http://farm9.staticflickr.com/8515/8489682002_9fcb64b961_b_d.jpg
>
> Any idea why this "jitter" ? Any pointers would be helpful.
>

You are using an analog pin for digital i/o so you need to set the=20
correct bit in ADPCFG, TRISA alone will not do it,  from the datasheet :
"
The ADPCFG register has a default value of 0x0000;
therefore, all pins that share ANx functions are analog
(not digital) by default."


You can see all kinds of weird behavior when the analog pins are not set=20
up correctly.
Mark

--=20
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