PLC Programming

Type Conversions...
TIME_TO/TIME_OF_DAY Conversions
Converting from the variable type TIME or TIME_OF_DAY to a different type:
The time will be stored internally in a DWORD in milliseconds (beginning with 12:00 A.M. for the
TIME_OF_DAY variable). This value will then be converted.
When you perform a type conversion from a larger to a smaller type, you risk losing some information
For the STRING type variable, the result is a time constant.
Examples in IL:
LD T#12ms
TIME_TO_STRING
ST str
LD T#300000ms
TIME_TO_DWORD
ST dw
LD TOD#00:00:00.012
TOD_TO_SINT
ST si
(*Result is 'T#12ms' *)
(*Result is 300000 *)
(*Result is 12 *)
Examples in St:
str :=TIME_TO_STRING(T#12ms); (* Result is T#12ms *)
dw:=TIME_TO_DWORD(T#5m); (* Result is 300000 *)
si:=TOD_TO_SINT(TOD#00:00:00.012); (* Result is 12 *)
Examples in FBD:
DATE_TO/DT_TO
Conversions
Converting from the variable type DATE or DATE_AND_TIME to a different type:
The date will be stored internally in a DWORD in seconds since Jan. 1, 1970. This value will then be
converted.
When you perform a type conversion from a larger to a smaller type, you risk losing some information
For STRING type variables, the result is the date constant.
Examples in St:
b :=DATE_TO_BOOL(D#1970-01-01); (* Result is FALSE *)
i :=DATE_TO_INT(D#1970-01-15); (* Result is 29952 *)
byt :=DT_TO_BYTE(DT#1970-01-15-05:05:05); (* Result is 129 *)
str:=DT_TO_STRING(DT#1998-02-13-14:20);
(* Result is
'DT#1998-02-13-14:20' *)
10-18 CoDeSys V2.3