/* modbus 主机实现*/

#include<stdint.h>
#include "crc.h"
#include "modbus-m.h"
#include "rtthread.h"

// 读取保持寄存器的值
// addr  寄存器地址
// id 丛机地址
// length 读取丛机数据长度
int modbus_m_read_regist(uint8_t id,uint16_t addr,uint16_t length,uint8_t * data)
{
	uint16_t index = 0,crc;
	data[index++] = id;
	data[index++] = 0x03;
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	data[index++] = (length >> 8) & 0x00FF;
	data[index++] = length & 0x00FF;
	crc = MX_CRC_CALC(data,index);
	data[index++] =  crc & 0x00FF;
	data[index++] = (crc >> 8) & 0x00FF;
	return index;
}

// 读取输入的值
// addr  寄存器地址
// id 丛机地址
// length 读取丛机数据长度
int modbus_m_read_input(uint8_t id,uint16_t addr,uint16_t length,uint8_t * data)
{
	uint16_t index = 0,crc;
	data[index++] = id;
	data[index++] = 0x04;
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	data[index++] = (length >> 8) & 0x00FF;
	data[index++] = length & 0x00FF;
	crc = MX_CRC_CALC(data,index);
	data[index++] =  crc & 0x00FF;
	data[index++] = (crc >> 8) & 0x00FF;
	return index;
}


// 写入寄存器
// addr  寄存器地址
// id 丛机地址
// length 读取丛机数据长度
int modbus_m_write_regist(uint8_t id,uint16_t addr,uint16_t key,uint8_t * data)
{
	uint16_t index = 0,crc;
	data[index++] = id;
	data[index++] = 0x06;
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	data[index++] = (key >> 8) & 0x00FF;
	data[index++] = key & 0x00FF;
	crc = MX_CRC_CALC(data,index);
	data[index++] =  crc & 0x00FF;
	data[index++] = (crc >> 8) & 0x00FF;
	return index;
}


//03 10 00 02 00 02 04 41 00 00 00
// 写入寄存器
// addr  寄存器地址
// id 丛机地址
// length 读取丛机数据长度
int modbus_m_write_mregist(uint8_t id,uint16_t addr,uint8_t *key,uint16_t size ,uint8_t * data)
{
	uint16_t index = 0,crc;
	data[index++] = id;
	data[index++] = 0x10;
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	data[index++] = (size >> 8) & 0x00FF;
	data[index++] = size & 0x00FF;
	data[index++] =  size * 2;
	for (int i =0;i < size * 2;i++)
	{
		data[index++] = key[i];
	}
	crc = MX_CRC_CALC(data,index);
	data[index++] =  crc & 0x00FF;
	data[index++] = (crc >> 8) & 0x00FF;
	return index;
}

// 写入寄存器
// addr  寄存器地址
// id 丛机地址
// length 读取丛机数据长度
int modbus_m_write_coil(uint8_t id,uint16_t addr,uint16_t key,uint8_t * data)
{
	uint16_t index = 0,crc;
	data[index++] = id;
	data[index++] = 0x05;
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	if (key == 1)
	{
	data[index++] = (addr >> 8) & 0x00FF;
	data[index++] = addr & 0x00FF;
	}
	else
	{
		data[index++] = 0x00;
		data[index++] = 0x00;
	}
	crc = MX_CRC_CALC(data,index);
	data[index++] =  crc & 0x00FF;
	data[index++] = (crc >> 8) & 0x00FF;
	return index;
}


MOD_T modbus_m_crc_check(uint8_t * data,int size )
{
	uint16_t rcrc = 0,ccrc;
	if (size < 4)
	{
		return MOD_ERR;
	}
		
	ccrc = MX_CRC_CALC(data,size-2);
	rcrc =  ((uint16_t)data[size-1] << 8 )+  (uint16_t)data[size-2];
	if (ccrc == rcrc )
		return MOD_OK;
	return MOD_ERR;
}