SLAU780 August 2018
To use an external emulator as a power source, use an emulator that supplies 3.3 V to pin 1 on the Arm 20-pin JTAG interface. When 3.3 V is supplied to the board from the emulator, disconnect the output of the onboard 3.3-V LDO (U5) from the 3.3-V power rail by removing the jumper on JP8. Figure 2 shows the location of JP8.
If USB host functionality is required from the onboard USB OTG connector, provide 5 V to the board through the external power header (J11) or the BoosterPack header (J3).