ProSoft Technology MVI69L-MBS - Manual (Page 124)

Reference MVI69L-MBS ♦ CompactLogix Platform
User Manual Communication Module
Page 124 of 154 ProSoft Technology, Inc.
January 6, 2014
7.4.1 Event Blocks
Blocks 1000 to 1255: Event Port 1
Event Command blocks send Modbus commands directly from the ladder logic to
the Master port. The Event Command is added to the high-priority queue and
interrupts normal polling so that this special command can be sent as soon as
possible.
Note: Overuse of Event Commands may substantially slow or totally disrupt normal polling. Use
Event Commands sparingly. Event Commands are meant to be used as one-shot commands
triggered by special circumstances or uncommon events.
Blocks 1000 to 1255: Request from Processor to Module
Offset Description
0 Write Block ID: 1000 to 1255 for a Port 1 command. The last 3 digits of the
command are used to specify the slave address to use for the command.
1 Internal address in the module to be used with the command.
2 Count parameter that determines the number of digital points or registers to
associate with the command.
3 Swap type for the data.
4 Modbus Function Code to be associated with the command.
5 Modbus address in the slave device to be used in the command.
6 to 239 Spare
Blocks 1000 to 1255: Response from Module to Processor
Offset Description
0 Read Block ID: 1000 to 1255 requested by the processor.
1 Write Block ID: To be used by the processor in its next Write block
2 Result of the event request. 1 = the command was placed in the command queue; 0
= no room was found in the command queue.
3 Number of commands in the command queue for the specified port.
4 to 239 Spare