Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 User Manual
Page 53

Using the 1775ĆMX
Memory Communication Module
Chapter 4
4-6
The MCM OPERATION menu contains an entry for each LIST function
listed in Table 4.D. These functions are a subset of those available when
using message instructions.
Table 4.D
LIST Functions
Command
Description
INACTIVE
The memory communication module stops both continuous
data transfers and continuous file transfers to the backup
processor.
FILE TRANSFER
The memory communication module transfers the selected
files from the primary to the backup processor continuously.
FILE SELECTION
Lets you select up to 16 files for use with the file transfer
function.
DATA TABLE XFER
The memory communication module continuously transfers
the entire data table, except the data table status section,
from the primary to the backup processor.
MEMORY DOWNLOAD
The memory communication module stops any data transfer
in progress and transfers the entire contents of PLCĆ3
memory from the primary to the backup processor.
LOCK SYSTEM
The memory communication module has the edit resource
for both the primary and backup processors. This protects
the ladder program in the current context from being edited
while in the run or test mode.
UNLOCK SYSTEM
The memory communication module releases the edit
resource for both the primary and backup processors.
ENABLE PROG COMP
The memory communication module compares the ladder
diagram program in the backup processor with the one in the
primary processor on a wordĆbyĆword basis.
DISABLE PROG COMP
The memory communication module prevents the execution
of the program compare function.
PROG COMP LIMITS
Lets you select specific sections of the ladder program to be
compared when
ENABLE PROG COMP
has been
selected.
BACKUP TO PRIMARY
DATA TRANSFER
Lets you transfer up to 16 words from the backup to the
primary processor.
The following sections describe each LIST command in detail.