User manual

Reference MVI56-HART ♦ ControlLogix Platform
User Manual HART Multi-drop Master Communication Module
Page 86 of 171 ProSoft Technology, Inc.
October 13, 2011
Write Block
These blocks of data transfer information from the ControlLogix processor to the module.
The following table describes the structure of the output image.
Offset Description Length
0 Write Block ID 1
1 to 200 Write Data 200
201 to 247 Spare 47
The Block Identification code defines the content of the data contained in the block. If the
code is set to -1 or 0, the data area contains no valid data. If the word contains a value
from 1 to 20, the data contained in the block should be placed in the appropriate position
of the module’s database. Under normal conditions, the value used for the write block
identification code should be that received in the read block from the module.
5.2.4 Command Control Blocks
Block identification codes greater than 9900 are utilized to perform special functions in
the module. Each control block recognized and used by the module is defined in the
following topics.
Block 9902: Command Control
The block 9902 identification code is used by the processor to enable a set of commands
that have their enable code set to 4 or 5 (one shot). The value referenced by the address
associated with the command, Enable DB Address, will be set to -1 to enable the
command for a one-shot (enable code 5) or continuous (enable code 4) execution. After
the command is executed, the module resets the register to 0 to disable the command for
the one-shot mode. The format for this command block is shown in the following table.
Word Offset in Block Data Field(s) Description
0 Block ID This field contains the value of 9902 identifying the
enable command to the module.
1 Port Number This is the HART port number (0 to 3) for the
command. Each port has its own command list.
2 Command
count
This field contains the number of commands To enable
in the command list. Valid values for this field are 1 to
60.
3 to 62 Command
Numbers to
enable
These 60 words of data contain the command numbers
in the command list to enable. The value referenced by
the Enable DB address associated with each command
will be set to -1.
63 to 247 Spare Not Used
There is no response to this block by the module.