cannnot halt target after reset

hi, i`m a newbie in arm7 microcontroller...

I have lpc2378stk dev board, and I use macgraigor wiggler Arm-JTAG debugger and while i use crosswork to download the code , I unable to download it.... everything went fine until I try to debug and i failed...

cannnot halt target after reset... stated, does anyone know where i wrong? what does it mean?

Anyone, please help me...