Communicating with non-arduino AVR over serial

i have arduino mega , wanted dive in , see how works following this tutorial atmega644 , usbasp programmer. after blinking led, felt next logical step communicate bytes on serial connection arduino. unfortunately, regardless of arduino receives random combination of 0 , 128 values.
things i've tried:

• reading serial data transmitted atmega644 second serial connection(since have mega), , softwareserial library(on 10 , 11 pins)


• changing baud rate no effect on random 0 , 180 values


• confirmed timing set correctly , 16mhz led flashing program @ 1 second intervals.

this cut down version of program on atmega644 sends bytes, have tried 6 other programs provided in serial communication tutorials no noticeable effect:

code: [select]


#include <stdio.h>
#include <avr/io.h>
#include <util/delay.h>
#define f_cpu 16000000
#define baud 9600
#include <util/setbaud.h>

void uart_init(void) {
   ubrr0h = ubrrh_value;
   ubrr0l = ubrrl_value;

   #if use_2x
       ucsr0a |= _bv(u2x0);
   #else
       ucsr0a &= ~(_bv(u2x0));
   #endif
   ucsr0c = _bv(ucsz01) | _bv(ucsz00);
   ucsr0b = _bv(rxen0) | _bv(txen0);
   
}
void uart_putchar(char c) {
   loop_until_bit_is_set(ucsr0a, udre0);
   udr0 = c;
}
int main(void) {    
   uart_init();
   
   for(;;;)
       uart_putchar('a');//i've tried sending incremental values try , affect random output
       
   return 0;
}

arduino sketch:

code: [select]


#include <softwareserial.h>
softwareserial portone(10,11);

void setup()
{
 serial.begin(9600);
 portone.begin(9600);
}

void loop()
{
 portone.listen();
 while (portone.available() > 0) {
   serial.println("data port one:");
   unsigned char inbyte = portone.read();
   serial.print(inbyte);
   serial.println();
 }
}

at point i'm positive i've configured wrong i've exhausted every possibility can think of. shed light on why might receiving random values of either 0 or 128, when change every condition possible in programs? try , simplify trying receive serial data through usb port usbasp sadly doesn't support serial communication avr computer.

thanks in advance

code: [select]

softwareserial portone(10,11,true);

why configuring inverted signals? give strange results. lose "true" part unless have reason.

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