System information

General Reference Guide Export Block Descriptors
RG-001-0-EN ver 1.5 eWON® - 20/03/2009 - ©ACT'L sa Page 171
8.3 Data Types description and syntax
A Data type defines what is exported from the eWON. The data type is defined by the $dt field followed by 2 uppercase letters. The $dt field is
mandatory for each "Export Block Descriptor" and usually the $ft (Format) field will also be present to define the output format of your data
(although a default format is defined for each data type).
For each Data type, a set of other fields must be provided (some are mandatory and others are optional).
Note:
If you specify an unused field (neither mandatory nor optional), it will then be ignored.
This section will describe the syntax for each data type with the specific features for each of them.
8.3.1 $dtHL [Historical Logging]
8.3.1.1 Export content
The Historical logging outputs the data from the File system for ONE or ALL the fields. The output format can be TEXT, HTML Table or BINARY.
The GRAPH format is also available IF only ONE Tag is specified.
A time range can also be specified for this export.
8.3.1.2 Detailed Example
8.3.1.3 Used Fields
8.3.1.4 Special parameters and fields
$st $et
If Last time is specified: ($stL or $etL): there is a last time logged for each Tag plus a last time logged for all Tags. If you specify a given Tag, its
own last time will be used. If a specific Tag is not requested, the export is performed for Tags concerned by historical logging and another last
time memory is used.
If the output format is graph: $et_0 should be used instead of default value, otherwise the graph would span up to 31/12/2030. For binary or text
output, the default value can be kept.
$dtHL $ftT $st_h4 $et_m0 $tnA1
$dtHL data type historical logging
$ftT output format requested is CSV
$st_h4 start time is current time – 4 hours
$et_0 end time is current time – 0 minutes Ù NOW
$tnA1 Tag history to output
Table 142: $dtHL detailed example
Fields Value if not specified
Mandatory
$dt
Optional
$ft Binary
$st 01/01/1970
$et 31/12/2030
$tn All
$ut No time update
$fn Export block descriptor
$ct Compression type
Table 143: $dt - used fields