ProSoft Technology MVI56-DFCMR - Manual (Page 71)

Reference MVI56-DFCMR ♦ ControlLogix Platform
DF1 Interface Module with Reduced Data Block
ProSoft Technology, Inc. Page 71 of 113
October 20, 2008
Command Control Block
Command control blocks place commands in the command list into the
command queue. Each port has a command queue of up to 100 commands. This
module services commands in the queue before the master command list. This
gives high priority to commands in the queue. Commands placed in the queue
through this mechanism must be defined in the master command list. Under
normal command list execution, the module will only execute commands with the
Enable parameter set to one or two. If the value is set to zero, the command is
skipped. Commands may be placed in the command list with an Enable
parameter set to zero. These commands can then be executed using the
command control blocks. One to six commands can be placed in the command
queue with a single request. The format of the block is shown in the following
table.
Command Control Request (Write Block)
Offset Description Length
0 5001 to 5006 or 5101 to 5106 1
1 Command index 1
2 Command index 1
3 Command index 1
4 Command index 1
5 Command index 1
6 Command index 1
7 to 41 Spare 35
Blocks in the range of 5001 to 5006 are used for Port 1, and blocks in the range
of 5101 to 5106 are used for Port 2. The last digit in the block code defines the
number of commands to process in the block. For example, a block code of 5003
contains 3 command indexes that are to be used with Port 1. The Command
index parameters in the block have a range of 0 to 99 and correspond to the
master command list entries.
The module responds to a command control block with a block containing the
number of commands added to the command queue for the port. The format of
the block is shown in the following table.
Command Control Response (Read Block)
Offset Description Length
0 Write Block ID 1
1 Number of commands added to command queue 1
2 to 40 Spare 39
41 5001 to 5006 or 5101 to 5106 1