ProSoft Technology MVI69-MCM - Manual (Page 51)

MVI69-MCM ♦ CompactLogix or MicroLogix Platform Configuring the MVI69-MCM Module
Modbus Communication Module User Manual
ProSoft Technology, Inc. Page 51 of 167
March 22, 2011
Read Register Start
0 to 4999
The Read Register Start parameter specifies the start of the Read Data area in
module memory. Data in this area will be transferred from the module to the
processor.
Note: Total user database memory space is limited to the first 5000 registers of module memory,
addresses 0 through 4999. Therefore, the practical limit for this parameter is 4999 minus the value
entered for Read Register Count, so that the Read Data Area does not try to extend above address
4999. Read Data and Write Data Areas must be configured to occupy separate address ranges in
module memory and should not be allowed to overlap.
Read Register Count
0 to 5000
The Read Register Count parameter specifies the size of the Read Data area of
module memory and the number of registers to transfer from this area to the
processor, up to a maximum of 5000 words.
Note: Total Read Register Count and Write Register Count cannot exceed 5000 total registers.
Read Data and Write Data Areas must be configured to occupy separate address ranges in
module memory and should not be allowed to overlap.
Write Register Start
0 to 4999
The Write Register Start parameter specifies the start of the Write Data area in
module memory. Data in this area will be transferred in from the processor.
Note: Total user database memory space is limited to the first 5000 registers of module memory,
addresses 0 through 4999. Therefore, the practical limit for this parameter is 4999 minus the value
entered for Write Register Count, so that the Write Data Area does not try to extend above address
4999. Read Data and Write Data Areas must be configured to occupy separate address ranges in
module memory and should not be allowed to overlap.