text: #ifndef __LIB_H__
  #define __LIB_H__
  
  #include "riscv.h"
  #include <stddef.h>
  #include <stdarg.h>
  
  extern void lib_delay(volatile int count);
  extern int  lib_putc(char ch);
  extern void lib_puts(char *s);
  
  #endif
  