TMS320F28069下载程序失败

Other Parts Discussed in Thread: TMS320F28069
我用的是TMS320F28069的板子,点击“debug”下载程序时出现了以下报错内容:

Error connecting to the target:
(Error -1015 @ 0x0)
Device is not responding to the request. Device may be locked, or the debug probe connection may be unreliable. Unlock the device if possible (e.g. use wait in reset mode, and power-cycle the board). If error persists, confirm configuration and/or try more reliable JTAG settings (e.g. lower TCLK).
(Emulation package 6.0.407.3)

想问一下有什么解决的办法。谢谢。