[Sdcc-user] ?ASlink-Warning-Undefined Global '_printf' referenced by module 'hello'

[Michael M. <mic...@gm...>]

Hi
how can I solve the Problem?
this is my Program
  #define MICROCONTROLLER_SAB80517
  #define MCS51REG_EXTERNAL_RAM
  #include <mcs51reg.h>
  #include <stdio.h>

  void main (void)=20
  {
    while (1)
    {
      printf ("Hello World\n");
    }
  }

  >sdcc  hello.c
  hello.c:3: error:mcs51reg.h: No such file or directory
  ?ASlink-Warning-Undefined Global '__sdcc_external_startup' referenced =
by module 'hello'
  ?ASlink-Warning-Undefined Global '_printf' referenced by module =
'hello'
  >

The Problem with the '__sdcc_external_startup' I solved with following =
code
unsigned char _sdcc_external_startup () { return 0; }

i don=B4t know what it does, but I read in the history about this. But I =
can=B4t find a solution for the _printf problem.
Thanks for your help.
Michael