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
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...) ?
And does the board have a proper reset circuit? Or just some variant of an RC reset?
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.
Tying the VBAT pin to 3.3V has fixed the problem.
Thanks for everyone's input - hope this can help someone else.