avr - ATmega128 - UCSROA undeclared (first use in this function) -

i have question atmega128 (uart) program sends hello message through uart.

the following code.

#include <avr/io.h>  void putch(unsigned char data) {     while((ucsroa & 0x20) == 0);     udr0 = data;     ucsroa |= 0x20; }  int main() {     unsigned char text[] = "hello! world!\r\n";     unsigned char = 0;      ddre = 0xfe;     ucsroa = 0x00;     ucsrob = 0x18;     ucsroc = 0x06;     ubrroh = 0x00;     ubrrol = 0x03;      while(text[i] != '\0')     putch(text[i++]);     return 0;  } 

this error messages.

build succeeded 0 warnings...  avr-gcc  -mmcu=atmega128 -wall -gdwarf-2 -std=gnu99   -df_cpu=7372800ul -os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums -md -mp -mt hello.o -mf dep/hello.o.d  -c  ../hello.c  ../hello.c: in function 'putch':  ../hello.c:5: error: 'ucsroa' undeclared (first use in function)  ../hello.c:5: error: (each undeclared identifier reported once  ../hello.c:5: error: each function appears in.)  ../hello.c: in function 'main':  ../hello.c:16: error: 'ucsroa' undeclared (first use in function)  ../hello.c:17: error: 'ucsrob' undeclared (first use in function)  ../hello.c:18: error: 'ucsroc' undeclared (first use in function)  ../hello.c:19: error: 'ubrroh' undeclared (first use in function)  ../hello.c:20: error: 'ubrrol' undeclared (first use in function)  make: *** [hello.o] error 1 build failed 8 errors , 0 warnings... 

i tested code other computers.
but, it's not working.
don't know how fix problem.

give me advice.
thanks.

its not

ucsroa

with letter "o", is

ucsr0a

with number 0.