ProSoft Technology MVI69-101S - Manual (Page 78)

MVI69-101S ♦ CompactLogix or MicroLogix Platform Reference
IEC 60870-5-101 Slave Communication Module
Page 78 of 149 ProSoft Technology, Inc.
March 16, 2009
Data contained in this database is paged through the input and output images by
coordination of the CompactLogix or MicroLogix ladder logic and the MVI69-
101S module's program. The read and write block identification codes in each
data block determine the function to be performed or the content of the data
block. The module uses the following block numbers:
Block Range Descriptions
0, -1 Status Block
1 to 67 Read or Write Data
1000 to 1067 Request Output Data from Processor
9958 Event Messages from CLX
9970 Set PLC time using module's time
9971 Set module's time using CLX time
9998 Warm-boot control block
9999 Cold-boot control block
Each image has a defined structure depending on the data content and the
function of the data transfer.
5.2.2 Normal Data Transfer
Normal data transfer includes the paging of the user data found in the module's
internal database in registers 0 to 4999 and the status data. These data are
transferred through read (input image) and write (output image) blocks. Refer to
the Module Configuration and Ladder Logic sections for a description of the
data objects used with the blocks and the ladder logic required. The structure
and function of each block is discussed in the following topics.
Read Block
These blocks of data transfer information from the module to the CompactLogix
or MicroLogix processor. The structure of the input image used to transfer this
data is shown below:
Offset Description Length
0 Read Block ID 1
1 Write Block ID 1
2 to (n+1) Read Data n
where
n = 60, 120, or 240 depending on the Block Transfer Size parameter (refer to the
configuration file).
The Read Block ID is an index value used to determine the location of where the
data will be placed in the CompactLogix or MicroLogix processor controller tag
array of module read data. The number of data words per transfer depends on
the configured Block Transfer Size parameter in the configuration file (possible
values are 60, 120, or 240).