I've got a new board with an LPC2378 on it, running a simple program for the moment. When I turn power on, about half the time the processor won't start - the oscillator doesn't come on, code isn't executing. Pressing the Reset button doesn't have any effect. I can't connect to it with ULINK in this state, either.
I have to turn power off, then back on, then it takes off without issue. Then if I cycle power again it's random whether it will work the next time or not. Once it starts working, it's fully functional.
Could this be a PLL setup issue? I'm using the supplied startup code, which waits for the oscillator to stabilize before going forward. Otherwise I'm thinking it's a problem with hardware...
Thanks
Tying the VBAT pin to 3.3V has fixed the problem.
Thanks for everyone's input - hope this can help someone else.
3.3V comes up in 200 microseconds.
Reset is a pushbutton to GND, with external pullup to 3.3V.
My next guess is that I've got VBAT floating, even though I'm not using the RTC.
And does the board have a proper reset circuit? Or just some variant of an RC reset?
I would start by checking your chip's power supply. Does it function in accordance with the user manual of the chip (voltage rise time etc...) ?
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