main.c

数字表头的应用介绍 数字表头的应用介绍

/*****************************************************************************
*
* Atmel Corporation
*
* File              : main.c
* Compiler          : IAR EWAAVR 2.28a/3.10c
* Revision          : $Revision: 1.13 $
* Date              : $Date: 24. mai 2004 11:31:20 $
* Updated by        : $Author: ltwa $
*
* Support mail      : [e-mail]
*
* Supported devices : All devices with a TWI module can be used.
*                     The example is written for the ATmega16
*
* AppNote           : AVR315 - TWI Master Implementation
*
* Description       : Example of how to use the driver for TWI master
*                     communication.
*                     This code reads PORTD and sends the status to the TWI slave.
*                     Then it reads data from the slave and puts the data on PORTB.
*                     To run the example use STK500 and connect PORTB to the LEDS,
*                     and PORTD to the switches. .
*
****************************************************************************/
#define MAIN_C

#include "includes.h"

#define TWI_GEN_CALL         0x00  // The General Call address is 0

// Sample TWI transmission commands
#define SLA_W 0xA0
#define SLA_R  0xA1

// Sample TWI transmission states, used in the main application.
#define SEND_DATA             0x01
#define REQUEST_DATA          0x02
#define READ_DATA_FROM_BUFFER 0x03

unsigned char TWI_Act_On_Failure_In_Last_Transmission ( unsigned char TWIerrorMsg )
{
// A failure has occurred, use TWIerrorMsg to determine the nature of the failure
// and take appropriate actions.
// Se header file for a list of possible failures messages.

// Here is a simple sample, where if received a NACK on the slave address,
// then a retransmission will be initiated.

  if ( (TWIerrorMsg == TWI_MTX_ADR_NACK) | (TWIerrorMsg == TWI_MRX_ADR_NACK) )
    TWI_Start_Transceiver();

  return TWIerrorMsg;
}


void main( void )
{
    unsigned char messageBuf[TWI_BUFFER_SIZE];
    int i;
    UsartInit();                //USART初始化
    TWI_Master_Initialise();   //TWI初始化
    PutStr("TWI initialise success!\r");
    SREG |= (1<<7);            //Enable_interrupt
    messageBuf[0] = SLA_W;
    messageBuf[1] = 0x00;
    messageBuf[2] = 0x10;
    for(i=3;i<TWI_BUFFER_SIZE;i++)
    {
        messageBuf[i]=i-3;
    }
    PutStr("Start to write data to 24c64!\r");
    delay_nms(1000);
    TWI_Start_Transceiver_With_Data( messageBuf, TWI_BUFFER_SIZE );
    delay_nms(100);
    messageBuf[0] = SLA_W;
    messageBuf[1] = 0x00;
    messageBuf[2] = 0x15;
    PutStr("Start to read data from 24c64!\r");
    delay_nms(1000);
    TWI_Start_Transceiver_With_Data( messageBuf, 3 );
    delay_nms(100);
    messageBuf[0] = SLA_R;
    TWI_Start_Transceiver_With_Data( messageBuf, TWI_BUFFER_SIZE-2 );
    // while(!TWI_statusReg);
    for(i=1;i<9;i++)
    {
      ;
    }
}