6261d，插入usb到电脑，屏幕亮起又灭掉，会是什么问题？
也抓取不到memorydump
如果usb插入充电器，就可以正常开机。
屏幕反复亮起又灭掉
追踪代码，发现已经跑到了任务初始化。 实在不知道下一步该怎么分析。
问题描述的有点不明确。关机情况下插入USB?开机指的仅仅是显示充电画面，还是到IDLE界面了?
启动到开机动画界面，然后就有黑屏了。
附上boot up trace.
Enter L1-cache init
Exit L1-cache init
Starting Application_Initialize()
Enter C library basic init
Exit C library basic init
Enter L1D init mode set
Exit L1D init mode set ... [ duration: 0 ms ]
Enter system intialization
Exit system intialization ... [ duration: 0 ms ]
Enter ARM us counter init
Exit ARM us counter init ... [ duration: 0 ms ]
Enter ARM OS Timer Sleep Mode init
Exit ARM OS Timer Sleep Mode init ... [ duration: 0 ms ]
Enter L1SM init
Exit L1SM init ... [ duration: 0 ms ]
Enter ARM OS Timer Sleep Mode init
Exit ARM OS Timer Sleep Mode init ... [ duration: 0 ms ]
Enter load DSP via iDMA
Exit load DSP via iDMA ... [ duration: 2 ms ]
Enter NFI reset
Exit NFI reset ... [ duration: 0 ms ]
Starting driver init phase1
Enter driver HISR init
Exit driver HISR init ... [ duration: 0 ms ]
Enter low power init
Exit low power init ... [ duration: 0 ms ]
Enter power down control init
Exit power down control init ... [ duration: 0 ms ]
Enter power management init
Exit power management init ... [ duration: 0 ms ]
Enter customized driver init
Exit customized driver init ... [ duration: 0 ms ]
Enter visual init
Exit visual init ... [ duration: 0 ms ]
Enter GPTI init
Exit GPTI init ... [ duration: 0 ms ]
Enter WDT init
Exit WDT init ... [ duration: 0 ms ]
Enter DMA init
Exit DMA init ... [ duration: 0 ms ]
Enter XOSC set
Exit XOSC set ... [ duration: 31 ms ]
Enter ADC init
Exit ADC init ... [ duration: 0 ms ]
Enter ACCDET init
Exit ACCDET init ... [ duration: 0 ms ]
Enter LCD init
Exit LCD init ... [ duration: 0 ms ]
Enter RTC HW init
Exit RTC HW init ... [ duration: 0 ms ]
Enter power ON init
PW_PowerInit: factor: PWRKEY: 0
PW_PowerInit: factor: CHRIN: 0
PW_PowerInit: factor: USBIN: 1
PW_PowerInit: factor: RTC_ALARM: 0
PW_PowerInit: factor: WDT: 1
PW_PowerInit: factor: NORMAL_RST_FG: 1
PW_PowerInit: factor: CHR_PWRON_FG: 0
PW_PowerInit: factor: USBMS_PWRON_FG: 1
PW_PowerInit: factor: RTC_PWRON_FG: 0
PW_PowerInit: factor: PRECHR_PWRON_FG: 0
PW_PowerInit: factor: SWITCH2IDLE_FG: 0
PW_PowerInit: factor: SWITCH2CHR_FG: 0
PW_PowerInit: factor: SWITCH2USB_FG: 0
PW_PowerInit: BMT.PWRon: 6
Exit power ON init ... [ duration: 156 ms ]
Enter UART1 init
Exit UART1 init ... [ duration: 0 ms ]
Enter UART2 init
Exit UART2 init ... [ duration: 0 ms ]
Enter UART3 init
Exit UART3 init ... [ duration: 0 ms ]
Driver init phase1 ... [ OK ]
Enter post driver init phase 1
Exit post driver init phase 1 ... [ duration: 1295 ms ]
Starting driver init phase2
Enter USB2UART init
Exit USB2UART init ... [ duration: 0 ms ]
Enter keypad init
Exit keypad init ... [ duration: 0 ms ]
Enter RTC SW init
Exit RTC SW init ... [ duration: 0 ms ]
Enter SIM init
Exit SIM init ... [ duration: 0 ms ]
Enter MSDC init
Exit MSDC init ... [ duration: 1 ms ]
Enter EINT SW Debounce init
Exit EINT SW Debounce init ... [ duration: 0 ms ]
Enter cipher/hash engine init
Exit cipher/hash engine init ... [ duration: 0 ms ]
Enter I2C init
Init I2C init ... [ duration: 0 ms ]
Driver init phase2 ... [ OK ]
Enter resource initialization
Exit resource initialization ... [ duration: 0 ms ]
Enter C library init
Exit C library init ... [ duration: 0 ms ]
Enter file system init
Exit file system init ... [ duration: 2 ms ]
Enter file system sanity check
Exit file system sanity check ... [ duration: 5 ms ]
Starting task init
Enter task init - INDX_NVRAM
Exit task init - INDX_NVRAM ... [ duration: 27 ms ]
Enter task init - INDX_TST
USB口驱动电流不足造成。 结贴。
哥们，怎么改好的，我也碰到这个问题了。谢谢！
电脑的USB口驱动电流不足，或者容易受到干扰。 更换稳定的电脑USB口。
多谢。我也为这个问题困扰了好久，有的时候出现，有的时候又是好的。AC充电是完全没问题的。
你们没改mtk的软件吗?
呵呵，这样的现象需要检查硬件了，开机电流虽然说很大，但是电池加USB还不能够提供足，有点高的吓人，除非电池本身就是坏的
查下VIO28和VIO18供电通路是否有干扰。