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9 years, 8 months ago.
External power
When I power the EA LPC11U35 QuickStart Board from a computer USB port everything is fine.
But when I power it with a 5V battery pack it does not boot. Only the green USB LED lights up. That also happens when I power it from a USB power supply.
So it only works when powering it from a real computer USB port. What could be wrong?
Edit: It was my fault because I used USBSerial which blocks the program before reaching main().
It does look like the board lacks protection diodes on 5V, so you can have external power or USB, but not both.
posted by geoffrey brown 28 Jan 2015