Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM - Manual (Page 133)

Publication AG-UM008C-EN-P - February 2005
Configuring MicroLogix 1100/1200/1500 Controllers 3-65
The number of DLS file elements depends upon the number of
queues specified in the application. The status bits and words are
described below.
Data Logging Enable (EN)
When the DLG instruction rung is true, the Data Logging Enable (EN)
is set (1) and the DLG instruction records the defined data set. To
address this bit in ladder logic, use the format: DLS0:Q/EN, where Q is
the queue number.
Data Logging Done (DN)
The Data Logging Done (DN) bit is used to indicate when the
associated queue is full. This bit is set (1) by the DLG instruction
when the queue becomes full. This bit is cleared when a record is
retrieved from the queue. To address this bit in ladder logic, use the
format: DLS0:Q/DN, were Q is the queue number.
Data Logging Overflow (OV)
The Data Logging Overflow (OV) bit is used to indicate when a record
gets overwritten in the associated queue. This bit is set (1) by the DLG
instruction when a record is overwritten. Once set, the OV bit remains
set until you clear (0) it. To address this bit in ladder logic, use the
format: DLS0:Q/OV, where Q is the queue number.
File Size (FSZ)
File Size (FSZ) shows the number of records that are allocated for this
queue. The number of records is set when the data log queue is
configured. FSZ can be used with RST to determine how full the
queue is. To address this word in ladder logic, use the format:
DLS0:Q.FSZ, where Q is the queue number.
Table 3.13 Data Log Status (DLS) File Elements
Control Element
Word 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
0
EN
(1) 0
DN
(2)
OV
(3) 0 0 0 0 0 0 0 0 0 0 0 0
1 FSZ = File Size (number of records allocated)
2 RST = Records Stored (number of records recorded)
(1) EN = Enable Bit
(2) DN = Done Bit
(3) OV = Overflow Bit