ccs5.5 printf

hi:

I use the 8168 board。

   1： I created an ordinary project, which according to a printf ("Hello world \n!"); I when running the program, the console can be displayed on the Hello world,If you change the print statements such as printf ("ffffffffff \n!"); there is no output in console.Change the stack size can be output, but the change in the output string has no output.If the output of a numerical case, change the stack size is of no use, how should I do in this case.

2： I created a new DSP project, LOG_PRINTF (&trave, "Hello world"); A8 connected, in connection with DSP, in the printf logs in formattedMsg is always showing the time information, and no output Hello world. how can I do, the output Hello world information.

THANK YOU