System information

General Reference Guide Export Block Descriptors
RG-001-0-EN ver 1.5 eWON® - 20/03/2009 - ©ACT'L sa Page 169
8.2.3 $st [Start Time] and $et [End Time]
These 2 fields are used to limit the time range of an export operation. $st and $et provide the start and end time of the export. The parameter
format is the same for both fields. There are 3 different formats for the $st, $et parameter:
• Relative time
• Absolute time
• From last $ut (see also “$ut [Update Time]” on page 170).
8.2.3.1 $st, $et with relative time
Syntax:
$st_([s]|[m]|[h]|[d])100 _ = back
(h,m,s,d = Hour, min, sec, day. 100 is the amount)
This represents a time regarding to the current time expressed in days, hour, minutes or seconds. If no letter is specified minutes are considered.
Examples:
8.2.3.2 $st, $et with absolute time
Syntax:
$stDDMMYYYY[[_HHMMSS][[_mmm][[_I][[_T]]]]]
Where:
When ALL the Tags are specified, the Tag values are output in chronological order. For the same time there can be 2 Tag values. In order to
reposition correctly in the file, it is necessary to provide the last Tag output during a previous export.
Examples:
8.2.3.3 $st , $et with Last time
By adding the $ut command in an Export Block Descriptor, you can ask the eWON to remember the time of the last point exported, this time can
be used for the next export.
The last time is reset when the eWON boots.
Syntax:
$stL
L is the time parameter meaning last time.
$st_m10 10 minutes in the past
$et_0 0 minutes in the past (= now)
$st_d2 2 days in the past
Table 139: $st with relative time examples
DDMMYYYY Means Day, Month, Year, 8 characters. This parameter is required.
HHMMSS Means Hour, Minute, Second, 6 characters. This parameter is optional (0 used by default)
mmm
Means milliseconds (000 to 999) 3 characters. This parameter is optional but if present, HHMMSS must also
be specified.
I
Means intra sec counter. This value is present when receiving a historical logging from the eWON. It can be
specified in export request to allow precise repositioning in the historical file. This parameter is optional, but if
present, HHMMSS and mmm must also be specified.
T
Means Tag id. As for I, this parameter is used for precise positioning in historical file. This parameter is
optional, but if specified, HHMMSS, mmm and I must be present also.
Table 140: $st parameters
$st01012000_120000 1 jan 2000 at 12 AM
$st01012000_120000_010 1 jan 2000 at 12 AM + 10 msec
Table 141: $st with absolute time examples