STM32 SWD 下载失败

从网上买的POS机，处理器是STM32F401CC，已引出SW接口，j-link识别，但下载失败。求大神指点原谅，刚注册没有积分

附上错误信息
Build Time Elapsed: 00:00:07
Load "D:\\Keil工程源文件\\ARM_STM32F401CCU6\\Output\\STM32F401CC.axf"
Set JLink Project File to "D:\Keil工程源文件\ARM_STM32F401CCU6\JLinkSettings.ini"
* JLink Info: Device "STM32F401CC" selected.
JLink info:
------------
DLL: V4.96d, compiled Jan 29 2015 11:45:37
Firmware: J-Link ARM-OB STM32 compiled Aug 22 2012 19:52:04
Hardware: V7.00
S/N : 20090928
Feature(s) : RDI,FlashDL,FlashBP,JFlash,GDBFull
* JLink Info: Found SWD-DP with ID 0x2BA01477
* JLink Info: Found SWD-DP with ID 0x2BA01477
* JLink Info: Found Cortex-M4 r0p1, Little endian.
* JLink Info: FPUnit: 6 code (BP) slots and 2 literal slots
* JLink Info: TPIU fitted.
* JLink Info: ETM fitted.
ROMTableAddr = 0xE00FF003
Target info:
------------
Device: STM32F401CC
VTarget = 3.300V
State of Pins:
TCK: 0, TDI: 0, TDO: 1, TMS: 0, TRES: 1, TRST: 0
Hardware-Breakpoints: 6
Software-Breakpoints: 8192
Watchpoints: 4
JTAG speed: 4000 kHz
Erase Failed！
Error: Flash Download failed - "Cortex-M4"

新板子第一次烧吗?用SEGGER的STM32工具解锁一下芯片呢