DSP采用TMS320DM6441，之前的PCB板仿真器连接ARM核和DSP核都正常，但是现在新做的板连接ARM核没问题，连接DSP失败，提示信息如下：
Error connecting to the target:
Error 0x80000240/-275
Fatal Error during: Initialization, OCS,
This error was generated by TI's USCIF driver.
SC_ERR_SCAN_POLL_BUSY <-275>
The attempt to poll a target device exceeded its timeout limit.
The utility or debugger has requested that a target device be
repeatedly accessed for a specific data or status value.
This has failed because the built-in limit for the maximum number
of attempts when polling the JTAG scan-path has been exceeded.
Board Name: DM6446 XDS560 Emulator
Cpu Name: C6400PLUS_0
Abort: Close Code Composer Studio.
Retry: Try to connect to the target again.
Cancel: Remain disconnected from the target
Diagnostic: Run diagnostic utility.
Error 0x80000240/-275
Fatal Error during: Initialization, OCS,
This error was generated by TI's USCIF driver.
SC_ERR_SCAN_POLL_BUSY <-275>
The attempt to poll a target device exceeded its timeout limit.
The utility or debugger has requested that a target device be
repeatedly accessed for a specific data or status value.
This has failed because the built-in limit for the maximum number
of attempts when polling the JTAG scan-path has been exceeded.
Board Name: DM6446 XDS560 Emulator
Cpu Name: C6400PLUS_0
Abort: Close Code Composer Studio.
Retry: Try to connect to the target again.
Cancel: Remain disconnected from the target
Diagnostic: Run diagnostic utility.
请问这是什么原因？
