自己做的板子，之前做的那块板子可以用swd下载和仿真，这次焊的就下载不了，这是为什么啊？而且我在设置debug调试的时候要过好久才能识别出来

JLink info:
------------
DLL: V4.15n, compiled Jun 18 2010 19:55:09
Firmware: J-Link ARM V8 compiled Nov 28 2014 13:44:46
Hardware: V8.00
S/N : 87461523
Feature(s) : RDI, FlashBP, FlashDL, JFlash, GDBFull

* JLink Info: Found SWD-DP with ID 0x1BA01477
* JLink Info: TPIU fitted.
* JLink Info:   FPUnit: 6 code (BP) slots and 2 literal slots
**JLink Warning: S_RESET_ST not cleared
**JLink Warning: CPU did not halt after reset.
* JLink Info: Core did not halt after reset, trying to disable WDT.
**JLink Warning: CPU did not halt after reset.
* JLink Info: Core did not halt after reset, trying to disable WDT.
**JLink Warning: CPU did not halt after reset.
**JLink Warning: S_RESET_ST not cleared
* JLink Info: Found SWD-DP with ID 0x1BA01477
**JLink Warning: S_RESET_ST not cleared
**JLink Warning: CPU did not halt after reset.
* JLink Info: Core did not halt after reset, trying to disable WDT.
**JLink Warning: CPU did not halt after reset.
* JLink Info: Core did not halt after reset, trying to disable WDT.
**JLink Warning: CPU did not halt after reset.
**JLink Warning: S_RESET_ST not cleared
***JLink Error: CPU not halted
to J-Link via USB.
ROMTableAddr = 0x0
**JLink Warning: CPU could not be halted