ProSoft Technology MVI46-MCM - Manual (Page 69)

MVI46-MCM ♦ SLC Platform Reference
Modbus Communication Module User Manual
ProSoft Technology, Inc. Page 69 of 108
March 29, 2011
Command Control Blocks (5001 to 5006 or 5101 to 5106)
Command Control blocks place commands from the command list into the
command queue. Each port has a command queue of up to 100 commands. The
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.
Block Request from Processor to Module
M1 Offset Description Length
7800 5001 to 5006 or 5101 to 5106 1
7801 Command Index 1
7802 Command Index 1
7803 Command Index 1
7804 Command Index 1
7805 Command Index 1
7806 Command Index 1
Blocks in the range of 5001 to 5006 are used for Port 1, while 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 for 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.
Block Response from Module to Processor
M0 Offset Description Length
0 5000 to 5006 or 5100 to 5106 1
1 Number of commands added to command queue 1