Serial communication between C51 and atmega64 and PROTEUS simulation design

Several registers used by 51 UART

SCON:SM0 SM1 SM2 REN RB8 TX8 ONLY

PCON: SMOD --   --      --      ---    ---    PD IDLE

T2CON: TF2 EXF2  RCLK  TCLK  EXEN2  TR2  C/_T  CP/_RL2

TH2,TL2

Baud rate: 9600bps

avr:atmega64's two USARTs

Registers used

Uart0 is used here, so the relevant registers should be set during initialization:

UCSR0A : RXC TXC OUTPUT UPE U2X MPCM

UCSR0C ：--  UMSEL UPM1 UPM0 USBS UCSZ1 UCSZ0 UCPOL

UBRR0H 、 UBRR0L、

UCSR0B ：RXCIE TXCIE HITS RXEN TXEN UCSZ2 RXB8 TXB8

Don't ask me what these mean, if you don't understand, go look it up in a book.

Proteus simulation is as follows:

The simulation results are shown in the figure below:

It should be noted that:

Because I can only select 8MHz in the CKSEL Fuse of atmega64 in the simulation, the initialization baud rate in the AVR program is calculated based on 8MHz. So simulation is simulation, pay attention to the actual application.

When the 51 MCU uses timer 1 to generate the baud rate, it is said in the book that in mode 2, the maximum can only reach 4800bps at 12MHz. Here we have to use timer 2. But it is also very useful. . The 8052 core is used in the simulation. . Otherwise, don't blame me if there is no response. .

Finally, I attached the program. Some variables are declared but not used. It was just an experiment.

51's:

#include "reg52.h"

#define AA 0x61
#define commun_symbol 0x31
sbit LED=P2^0;
unsigned char Tx[]={"my name is seven!"};
void uart_init(void)
{
SCON   = 0x50;
RCAP2H = 0xFF;
RCAP2L = 0xD9;
TH2    = 0xFF;
TL2    = 0xD9;
T2CON  = 0x34;

}

void uart_send(unsigned char byData)
{
TI=0;
SBUF=byData;
while ( TI == 0 ) ;
TI=1;
} }

unsigned char uart_receive(void)
{
RI=0;
while(RI==0);
RI=1;
return(SBUF);
}

void main()
{
unsigned char byBuff,i;
uart_init();
uart_send(commun_symbol);
while(1)
{


byBuff=uart_receive();
LED=1;
if(byBuff==0x31)
{
for(i=0;i<20;i++)
{
P1=byBuff;
uart_send(Tx[i]);
}
}
}

}

Program for atmega64:

Two files, one is to modularize the function, and the other is the main function, calling (- -! Recently I have become accustomed to modularizing the program...)

//------------------uart.c---------------------

//----The communication function is modularized here------------

#include

void uart0_init(void)
{
UCSR0B = 0x00; //disable while setting baud rate
UCSR0A = 0x00;
UCSR0C = 0x06;
UBRR0L = 0x33; //set baud rate lo
UBRR0H = 0x00; //set baud rate hi
UCSR0B = 0x18;
}

void uart0_Transmit( unsigned char da ta )
{
/* Wait for empty transmit buffer */
while ( !( UCSR0A & (1< ;
/* Copy ninth bit to TXB8 */
UCSR0B &= ~(1< //if ( da ta & 0x0100 )
//UCSR0B |= (1< /* Put da ta into buffer, sends the da ta */
UDR0 = da ta;
}

unsigned char uart0_Receive( void )
{
/* Wait for receiving data*/
while ( !(UCSR0A & (1< ;
/* Get and return data from the buffer*/
return UDR0;
}

//--------------main.c-----------

//--------------------------------

#include
#include "spi.h"
#define commun_symbol 0x31

//-----------send a commun_symbol-----
//-----------receive a commun_symbol--
//      <--no,continue receive||||||yes-->receive the da ta and send
void main()
{
unsigned char bybuff;
DDRB=0xff;
PORTB=0xff;
uart0_init();
{

do
{
bybuff=uart0_Receive();
}
while (bybuff!=commun_symbol);//commun_symbol);
while(1)
{

uart0_Transmit(bybuff);
bybuff=uart0_Receive();
PORTB=(0xff|bybuff);
}
}
}