modbus.h

00001 /*
00002   modbus  comuunication class
00003    By modular-2 team 2018/8/3
00004   modbus  mode=RTU master/salve
00005   usage:
00006   master mode:
00007      sendQuery
00008      waitResponse
00009   salve mode:
00010         waitQuery
00011         sendResponse
00012    */
00013 #ifndef MODBUS_H
00014 #define MODBUS_H
00015 #include "mbed.h"
00016 class Modbus
00017 {
00018     public:
00019       Modbus(PinName tx, PinName rx,PinName txEnable, int baud);
00020       bool sendQuery(uint8_t address,uint8_t function,uint16_t startAddress,uint16_t points);
00021       int  waitResponse(uint8_t *data);
00022       bool  waitQuery(uint8_t &address,uint8_t &function,uint16_t &startAddress,uint16_t &points);
00023       bool sendResponse(uint8_t *data,uint8_t length); 
00024     private:
00025         uint8_t sbuf[32];
00026         uint8_t rbuf[32];
00027         Serial rs485;
00028         DigitalOut dir;
00029         uint8_t _address;
00030         uint8_t _function;
00031         uint16_t _startAddress;
00032         uint16_t _points;
00033         unsigned int  calculateCRC16( uint8_t *puchMsg,unsigned int  usDataLen);
00034     };
00035 #endif