ProSoft Technology MVI69L-MBTCP - Manual (Page 142)

Reference MVI69L-MBTCP ♦ CompactLogix Platform
User Manual Communication Module
Page 142 of 152 ProSoft Technology, Inc.
January 6, 2014
7.4.15 Pass-through Formatted Block for Function 15
Block 9959: Pass-through Formatted Block for Function 15
When the module receives a function code 15 in pass-through mode, the module
will write the data using block ID 9959 for multiple-bit data. First the bit mask
clears the bits to be updated. This is accomplished in RSLogix 5000 by ANDing
the inverted mask with the existing data.
Next, the new data ANDed with the mask is ORed with the existing data. This
protects the other bits in the INT registers from being affected.
Block 9959: Request from Module to Processor
Offset Description
0 Block ID 9959
1 Block ID 9959
2 Length in words
3 Data address
4 to 28 Modbus Data
29 to 53 Bit mask to use with the data set. Each bit to be considered with the data set will
have a value of 1 in the mask. Bits to ignore in the data set will have a value of 0
in the mask.
54 to n Spare
The ladder logic will be responsible for parsing and copying the received
message and performing the proper control operation as expected by the Client
device. The processor must then respond to the pass-through control block with
a write block with the following format.
Block 9959: Response from Processor to Module
Offset Description
0 Block ID 9959
1 to n Spare
This will inform the module that the command has been processed and can be
cleared from the pass-through queue.