Re: Renesas R8C Start up problem




"icegray" <usrdr@xxxxxxxxxxx> wrote in message
news:1129374479.298473.33730@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> there is a capacitor between reset pin and gnd, also there are 10uF
and
> some 100nF between Vcc and GND. all component power line is same.
> Xout pin -one pin of oscillator- connected to CPLD.
>
> What a stupid problem.

Maybe the problem is not with the Reset pull-up, but with Vcc ramping up
too slow. 10uF is not extremely large, but if power leads are long the
LC combination may make Vcc ramp up too slow when you apply power. I've
had problems with this when tinkering around and using long, skinny clip
leads to connect power. Also perhaps not enough capacitance on external
osc to start reliably.

.



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