Test/RTUSlave.c

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h> 

#include <modbus.h>

int dataProessing( uint8_t *query , modbus_mapping_t* map ) ;

int main(void)
{
	int ret = 0;

	modbus_t* ctx = NULL;
	modbus_mapping_t* map = NULL;

	uint8_t query[MODBUS_RTU_MAX_ADU_LENGTH];


	ctx = modbus_new_rtu("/dev/ttyAS3", 115200 , 'N', 8, 1);
	if (NULL == ctx)
	{
		fprintf(stderr, "New Rtu Error: %s\n", modbus_strerror(errno));
		return 1;
	}


	ret = modbus_set_slave( ctx, 1 );
	if (-1 == ret)
	{
		printf("设置从机地址失败.. %s\n", modbus_strerror(errno));
		modbus_free(ctx);
		return 1;
	}
#if  0
	ret = modbus_set_debug(ctx, TRUE);
	if (-1 == ret)
	{
		printf("modbus_set_debug failed...\n");
		modbus_free(ctx);
		return 1;
	}
#endif 


	ret = modbus_connect(ctx);
	if (-1 == ret)
	{
		fprintf(stderr, "打开串口失败: %s\n", modbus_strerror(errno));
		modbus_free(ctx);
		return 1;
	}



	map =  modbus_mapping_new_start_address( 0 , 0 , 0 , 0 , 30000 , 24 , 40000 , 135 ) ;
	if (NULL == map)
	{
		fprintf(stderr, "Error: mapping %s\n", modbus_strerror(errno));
		modbus_free(ctx);
		return 1;
	}

	for(int i = 0 ; i < 24 ; i++)
	{
		map->tab_registers[i] = i ;
	}

	for(int i = 0 ; i < 135 ; i++ )
	{
		map->tab_input_registers[i] = i * 2 ;
	}

	while (1)
	{
		map->tab_registers[0]++ ;
		memset(query, 0, sizeof(query));

		//获取查询请求报文
		ret = modbus_receive(ctx, query);
		if (ret >= 0)
		{
			//恢复响应报文
			modbus_reply(ctx, query, ret, map);
			dataProessing( query , map ) ;
		}
		else
		{
			printf("Connection close\n");
		}
	}

	printf("Quit the loop: %s\n", modbus_strerror(errno));


	modbus_mapping_free(map);

	modbus_close(ctx);
	modbus_free(ctx);

	return 0;
}


int dataProessing( uint8_t *query , modbus_mapping_t* map ) 
{
	uint16_t address ;
	uint16_t address1 ;
	uint16_t address2 ;

	uint16_t count ;
	uint16_t count1 ;
	uint16_t count2 ;
#if 0
	printf("\n=====================query start======================\n") ;
	for(int i = 0 ; i < MODBUS_RTU_MAX_ADU_LENGTH ; i++)
	{
		printf( "%d\t" , query[i] ) ;
	}
	printf("\n====================query end==========================\n") ;

	return 0 ;
#endif 
	printf("\n=============================================================\n") ;
	printf("从机设备地址为:%d\n" , query[0] ) ;
	if( query[1] == 3 )
	{
		printf("03 读取Read Holding Registers寄存器\n") ;
	}
	else if( query[1] == 4 )
	{
		printf("04 读取Read Input Registers寄存器\n") ;
	}
	address1 = query[2] << 8 ;
	address2 = query[3] & 0x00ff ;
	address  = address1 | address2 ;
	printf("读取的起始地址为:%d\n" , address) ; 

	count1 = query[4] << 8 ;
	count2 = query[5] & 0x00ff ;
	count  = count1 | count2 ;
	printf("读取的起始地址为:%d\n" , count) ; 

	printf("----------tab_registers----------\n") ;
	for(int i = 0 ; i < 24 ; i++)
	{
		printf("%d\t" , map->tab_registers[i] ) ;
	}
	
	printf("\n----------tab_input_registers----------\n") ;
	for(int i = 0 ; i < 135 ; i++ )
	{
		printf("%d\t" , map->tab_input_registers[i] ) ;
	}
	printf("\n=====================================================================\n" ) ;
	
	return 0 ;
}