My board works most of the time are very good，but one time i power down the board when ble connecting and data transmitting，the board can't work when power on.and i can't do anything to the board. after fonud the problem ，i tried about 200 times，and the problem happens again at 187th times. the board use two Batteries(1.5V one battery). is the Voltage instability when power on causes the program to run somewhere not right？ is there any way to protect the flash?
