我正在使用XDS560 V2 jtag工具调试i的tci6616芯片，之前USB连接一切正常，不过我升级了JTAG工具的固件之后，提示如下错误：
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[Start: Spectrum Digital XDS560V2 STM USB Emulator_0]
Execute the command:
%ccs_base%/common/uscif/dbgjtag.exe -f %boarddatafile% -rv -o -F inform,logfile=yes -S pathlength -S integrity
[Result]
-----[Print the board config pathname(s)]------------------------------------
C:\Users\wepan\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 'sd560v2u.out'.
Loaded FPGA Image: C:\ti\ccsv6\ccs_base\common\uscif\xds560v2pro.xsvf
The library build date was 'Jul 27 2016'.
The library build time was '17:21:41'.
The library package version is '6.0.407.3'.
The library component version is '35.35.0.0'.
The controller does not use a programmable FPGA.
E_RPCENV_IO_ERROR(-6) No connection: DTC_IO_Receive::dtc_io
E_RPCENV_IO_ERROR(-6) No connection: DTC_IO_Receive::dtc_io
-----[An error has occurred and this utility has aborted]--------------------
This error is generated by TI's USCIF driver or utilities.
The value is '-252' (0xffffff04).
The title is 'SC_ERR_ECOM_OPERATE'.
The explanation is:
An attempt to operate the USCIF interface via USCIF ECOM has failed.
[End: Spectrum Digital XDS560V2 STM USB Emulator_0]
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Firmware version 2.2.0.5
我已经按照说明上的文档设置
dtc_conf set _bootForce=true
dtc_conf set _fpgaForceLoad=false
但是现在每次发送命令都是上述结果，请问该怎么解决，谢谢！
补充一下：USB status 测试时，usb test loopback 10次 passed
