ProSoft Technology MVI69-MCM User Manual
Page 109

MVI69-MCM ♦ CompactLogix or MicroLogix Platform
Reference
Modbus Communication Module
User Manual
ProSoft Technology, Inc.
Page 109 of 167
March 22, 2011
Data contained in this database is paged through the input and output images by
coordination of the CompactLogix or MicroLogix ladder logic and the MVI69-
MCM module's program. Up to 242 words of data can be transferred from the
module to the processor at a time. Up to 241 words of data can be transferred
from the processor to the module. The read and write block identification codes
in each data block determine the function to be performed or the content of the
data block. The block identification codes used by the module are listed below:
Block Range
Descriptions
-1
Status Block
0
Status Block
1 to 84
Read or write data
1000
Event Port 1
2000
Event Port 2
3000 to 3001
Port 1 slave polling control
3002 to 3006
Port 1 slave status
3100 to 3101
Port 2 slave polling control
3102 to 3106
Port 2 slave status
5000 to 5006
Port 1 command control
5100 to 5106
Port 2 command control
9958
Function Code 5 data formatted Pass-Thru Control Blocks
9956 and 9957
Function Code 6 and 16 (Floating-point) data formatted Pass-Thru Control
Block
9959
Function Code 15 data formatted Pass-Thru Control Block
9998
Warm-boot control block
9999
Cold-boot control block
Each image has a defined structure depending on the data content and the
function of the data transfer.