Re: Renesas R8C Start up problem

icegray wrote: 
Hi,
I have used LM1086-3.3 lowdrop regulator and R8C cpu. Reset circuit is
only pull-up.
CPU doesn't start up right. External oscillator doesn't run when I turn
on  power. If I reset the CPU externaly everthing is OK.
Can you recommend something?

At least in R8C/1x series the external osc is not supposed to start when you reset the CPU. It must be started by firmware.
Also, the built-in reset circuit in R8C/11 and /13 is designed to operate at +5V - check is parameters in the data sheet. For 3V operation an external RC circuit is needed.
.

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