Reading and writing of TIME/DATE variables

Download: Reading and writing of TIME/DATE variables

The PLC contains the TIME variable MAIN.Time1 and the DT variable MAIN.Date1. This example shows how to read, write and display those variables:

#include <stdio.h>
#include <windows.h>
#include <tchar.h>
#include <time.h>

// ADS headers for TwinCAT 3
#include "C:\TwinCAT\3.0\AdsApi\TcAdsDll\Include\TcAdsDef.h"
#include "C:\TwinCAT\3.0\AdsApi\TcAdsDll\Include\TcAdsAPI.h"

#define TIME_LENGHT 56
#define DATE_LENGHT 62
#define MON_START 1
#define YEAR_START 1900

int _tmain(int argc, _TCHAR* argv[])
{
    long lErr, lPort;
    long lTime, lMs, lSek, lMin, lHour, lDay; 
    AmsAddr Addr;
    PAmsAddr pAddr = &Addr;
    DWORD dwTime, dwDate;
    ULONG lHdlTime, lHdlDate; 

// Declare PLC variable
    char szPlcTime []={"MAIN.Time1"};
    char szPlcDate []={"MAIN.Date1"};

// Open the communication
    lPort = AdsPortOpen();
    lErr = AdsGetLocalAddress(pAddr);
    if(lErr) printf_s((char*)"Error: Getting local adress: 0x%i \n", lErr);
    pAddr->port = AMSPORT_R0_PLC_RTS1;

// Get variable handle
    lErr = AdsSyncReadWriteReq(pAddr, ADSIGRP_SYM_HNDBYNAME, 0x0, sizeof(lHdlTime), &lHdlTime, sizeof(szPlcTime), szPlcTime);
    lErr = AdsSyncReadWriteReq(pAddr, ADSIGRP_SYM_HNDBYNAME, 0x0, sizeof(lHdlDate), &lHdlDate, sizeof(szPlcDate), szPlcDate);

// Read from MAIN.Time1
    lErr = AdsSyncReadReq(pAddr, 
                            ADSIGRP_SYM_VALBYHND,     // IndexGroup 
                            lHdlTime,             // IndexOffset
                            0x4,                         // Size of DWORD
                            &dwTime);
    if(lErr) printf_s((char*)"Error: Read time variable: 0x%i \n", lErr);

    //Convert DWORD to Time
    lTime = (long)dwTime;
    lMs     = (lTime % 1000);
    lSek = (lTime / 1000) % 60;
    lMin = (lTime / 60000) % 60;
    lHour = (lTime / 3600000) % 24;
    lDay = (lTime / 86400000) % 365;

    wchar_t szTime[TIME_LENGHT];
     wsprintf(szTime, L"Time from PLC: %dd %dh %dm %ds %dms \n", 
                        lDay, 
                        lHour, 
                        lMin, 
                        lSek, 
                        lMs);
    wprintf_s(szTime);

//Write to MAIN.Time1
    //Manipulate DWORD for demonstration
    dwTime += 3600000; //Add 3600000ms (One hour)

    //AdsWrite
    lErr = AdsSyncWriteReq(pAddr,
                            ADSIGRP_SYM_VALBYHND, //IndexGroup 
                            lHdlTime,         //IndexOffset
                            0x4, 
                                   &dwTime);
    if(lErr) printf_s((char*)"Error: Write time variable: 0x%i \n", lErr);

//Read from MAIN.Date1
    //AdsRead
    lErr = AdsSyncReadReq(pAddr, 
                            ADSIGRP_SYM_VALBYHND, //IndexGroup 
                            lHdlDate,         //IndexOffset
                            0x4, 
                            &dwDate);
    if(lErr) printf_s((char*)"Error: Read date variable: 0x%i \n", lErr);
    
    //Convert long to date
    time_t tDate(dwDate);
    tm tmDate; 
    
    gmtime_s(&tmDate, &tDate);

    wchar_t szDate[DATE_LENGHT];
    wsprintf(szDate, L"Date from PLC: %d/%d/%d %d:%d:%d \n", 
                tmDate.tm_mday, 
                tmDate.tm_mon + MON_START, 
                tmDate.tm_year + YEAR_START, 
                    tmDate.tm_hour,
                tmDate.tm_min, 
                tmDate.tm_sec);
    wprintf_s(szDate);

//Write to MAIN.Date1
    //Manipulate DWORD for demonstration
    dwDate += 3600; //Add 3600s (One hour)

    //AdsWrite 
    lErr = AdsSyncWriteReq(pAddr, 
                            ADSIGRP_SYM_VALBYHND, //IndexGroup 
                            lHdlDate,         //IndexOffset
                            0x4, 
                            &dwDate);
    if(lErr) printf_s((char*)L"Error: Write time variable: 0x%i \n", lErr);

//Releases handles of plc variable
    lErr = AdsSyncWriteReq(pAddr, ADSIGRP_SYM_RELEASEHND, 0, sizeof(lHdlTime), &lHdlTime); 
    if (lErr) printf("Error: AdsSyncWriteReq: %d \n", lErr);
    lErr = AdsSyncWriteReq(pAddr, ADSIGRP_SYM_RELEASEHND, 0, sizeof(lHdlDate), &lHdlDate); 
    if (lErr) printf("Error: AdsSyncWriteReq: %d \n", lErr);

//Close the communication
    lErr = AdsPortClose();
    if(lErr) printf_s((char*)L"Error: Closing connection: 0x%i \n", lErr);

    printf_s("\nPress enter to exit..");
    getchar();
}