I'm using a 430F5529 and I'm having an issue where the unit enters the boot loader when it is powered through a USB cigarette lighter adapter.
When I plug the unit into a PC it starts normally. When I plug the cigarette lighter adapter into the vehicle first, and then connect the unit to the USB port, it also starts normally.
However, then I first plug the USB connector into the cigarette lighter adapter and then the adapter into the vehicle, the unit enters the BSL.
The hardware is pretty standard. 1.4K from D+ to PUR. 1M from D+ to GND. Pushbutton switch in series with 100 ohm between VUSB and PUR.
I'm guessing it has something to do with PUR being high while the power supply comes up?
Anybody seen this before, and any suggestions on how to prevent it?
Thanks in advance,
Paul.