TI中文支持网CCS版本：V7.2
仿真器：XDS200
TI芯片：AM5728
以下是连接的报错信息：
[Start: Texas Instruments XDS2xx USB Debug Probe_0]
Execute the command:
%ccs_base%/common/uscif/dbgjtag -f %boarddatafile% -rv -o -S integrity
[Result]
—–[Print the board config pathname(s)]————————————
C:\Users\taozi\AppData\Local\TEXASI~1\CCS\
ti\0\0\BrdDat\testBoard.dat
—–[Print the reset-command software log-file]—————————–
This utility has selected a 560/2xx-class product.
This utility will load the program 'xds2xxu.out'.
The library build date was 'May 23 2017'.
The library build time was '19:03:48'.
The library package version is '6.0.628.3'.
The library component version is '35.35.0.0'.
The controller does not use a programmable FPGA.
The controller has a version number of '13' (0x0000000d).
The controller has an insertion length of '0' (0x00000000).
This utility will attempt to reset the controller.
This utility has successfully reset the controller.
—–[Print the reset-command hardware log-file]—————————–
This emulator does not create a reset log-file.
—–[An error has occurred and this utility has aborted]——————–
This error is generated by TI's USCIF driver or utilities.
The value is '-233' (0xffffff17).
The title is 'SC_ERR_PATH_BROKEN'.
The explanation is:
The JTAG IR and DR scan-paths cannot circulate bits, they may be broken.
An attempt to scan the JTAG scan-path has failed.
The target's JTAG scan-path appears to be broken
with a stuck-at-ones or stuck-at-zero fault.
[End: Texas Instruments XDS2xx USB Debug Probe_0]
什么原因导致连接不成功，一直没有解决，这个问题有人能帮助我吗？
另外我发现一个我不懂的地方，在原理图中JTAG_RSTn一直都是拉低的：
但是我在手册中又看到说有拉高，最后才是拉低，会不会是这个地方引起的：
HG：
参考设计应该没有问题
The target's JTAG scan-path appears to be brokenwith a stuck-at-ones or stuck-at-zero fault.
这个说明有信号被强拉高或强拉低了。
Shine：
回复 HG:
TRST信号加下拉电阻是对的。TRST是由仿真器把它拉高拉地产生复位信号。
量一下JTAG的各个信号是否都正确？
Z T：
回复 Shine:
你好，我现在正在准备测量各个管脚的信号，但是我不知道各个管脚正常的信号，因没有这方面的资料文档可以查看，你能帮助我吗？
Shine：
回复 Z T:
TRST有个低到高的时序，EMUx是高电平，TDO, TDI, TCLK可以看一下数据手册上JTAG的时序图。Figure 7-110. JTAG Timinghttp://www.ti.com/lit/ds/symlink/am5728.pdf
