It is amazing that the file IO subroutines still work in DSP simulation even in JTAG emulation. But when my programme becomes large, it seems that fread and fwrite functions have some problems. Sometimes, fread can not read data from the file locating at the PC side, and sometimes fwrite can not write data into the file. Can anyone tell me what happens when I call fread and fwrite functions in my dsp programme? Thanks liqiyue