自己做的板子，有时能连接上，有时连接不上，连不上时报错信息如下：
Error connecting to the target:
Error 0x80000240/-505
Fatal Error during: Initialization, OCS,
This error was generated by TI's USCIF driver.
SC_ERR_TEST_AUTOMATIC3 <-505>
The user selected phase-three auto-range frequency failed the scan-path test.
The utility or debugger requested the JTAG controller and cable,
that generate the JTAG clock, to use a user-selected feature or algorithm. The built-in scan-path reliability test has failed.
This indicates that the JTAG controller and its cable cannot reliably communicate with the target system using that feature or algorithm.
Try using the legacy frequency or a known good specific frequency.
用的10M的有源晶振，感觉像是时钟的问题，是不是频率有点低了？
