hi

how to set time in the plc i.e. from SCADA:

NOTE: parts of code can be shown as LAD
NOTE: "HMISCADA".GENERAL.HS_xxx holds date and time SETPOINT from scada
             (elements as int)
NOTE: "HMISCADA".GENERAL.H_DATE_TIME is current PLC date and time for local HMIs

// Temp Variables

DateTime : DateAndTime // Date_And_Time prepared from data provided by SCADA
RTC_RESULT : Int; // Result from RTC functions
NoRequest : Bool; //

// NW1: Check if we need to synchronize.
// Check if we need to synchronize. if not function copies PLC time
// to packed tag for local HMIs and terminates.

A(
L     "HMISCADA".GENERAL.HS_MONTH // Month from SCADA, 0=do not synchronize
L     0
==I
)
JNB   _001
CALL  "READ_CLK"
RET_VAL:=#RTC_RESULT
CDT    :="HMISCADA".GENERAL.H_DATE_TIME
_001: A     BR
SAVE
BEC

// PSEUDOCODE:
// if ("HMISCADA".GENERAL.HS_MONTH==0) THEN
//     CALL READ_CLK("HMISCADA".GENERAL.H_DATE_TIME); << read clock

// NW2: generates packed DT [s,ms and day of week are always 0]          
// DT is a byte structure:
// Byte 0: Year [90..89->1990..2089]; Byte 1: Month [01..12]; Byte 2: Day[1..31];
// Byte 3: Hour [0..23]; Byte 4: Minute [0..59]; Bytes 5..7: s, ms and day of week

// YEAR [90 .. 89 --> 1990 -> 2089]
L     "HMISCADA".GENERAL.HS_YEAR  // Year as 4 digits from Citect
L     2000                        // take 2000
-I                                // to get value 2000..2089-->00..89
T     LB     0                    // store in local bit [will be from 0]

L     LB     0                    // Check for error [year 1990..1999->90..99]
L     0
<I                                // if negative yeat is below 2000
JCN   Y_OK                        // if positive jump-ignore!
L     "HMISCADA".GENERAL.HS_YEAR  // Year as 4 digits from Citect
L     1900                        // take 1900
-I                                // to get 1990..1999 -> 90..99
T     LB     0                    // store in local bit [will be from 90 to 99]

Y_OK: L     LB     0                    // Convert Year to BCD
ITB
T     LB     0

// Month
L     "HMISCADA".GENERAL.HS_MONTH // Month from Citect as 1..12
ITB
T     LB     1
// Day
L     "HMISCADA".GENERAL.HS_DAY   // Day from Citect as 1..31
ITB
T     LB     2
// Hour
L     "HMISCADA".GENERAL.HS_HOUR  // Hour from Citect as 0..23
ITB
T     LB     3
// Minute
L     "HMISCADA".GENERAL.HS_MINUTE    // Minute from Citect as 0..59
ITB
T     LB     4
// Clear Seconds, Miliseconds and Day Of Week - SCADA synchronizes when seconds=00
L     0
T     LB     5                    // Seconds to 0
T     LB     6                    // ms to 0
T     LB     7                    // ms and day of week to 0
// Clear SCADA time tags to indicate synchronization performed
T     "HMISCADA".GENERAL.HS_YEAR
T     "HMISCADA".GENERAL.HS_MONTH
T     "HMISCADA".GENERAL.HS_DAY
T     "HMISCADA".GENERAL.HS_HOUR
T     "HMISCADA".GENERAL.HS_MINUTE

// NW3: Synchronize Clock - apply time from SCADA
CALL  "SET_CLK"
PDT    :=#DateTime
RET_VAL:=#RTC_RESULT
A     BR
SAVE
BEC