Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual User Manual
Page 104
Message Packet Formats
Chapter 5
5-25
Physical Write
This command writes bytes of data into the PC data table or program
memory. Use this command to download a computer file into PLC
memory.
Use the SIZE field to specify the number of bytes to be written. To
specify a number of PC words, SIZE should be an even value because PC
words are two bytes long.
Command Format:
Reply Format:
TNS
STS
CMD
03
SRC
DST
TNS
STS
CMD
43
SRC
DST
ADDR
DATA — Max. of 242 Bytes
PLC-2 Commands
PLC-2 stations can execute all of the commands in the basic command
set. They can also execute the following commands, which apply only to
PLC-2 Family controllers:
Enter Download Mode
Enter Upload Mode
Exit Download/Upload Mode
Physical Read
Physical Write
Set Data Table Size
The above commands are privileged. This means that only a computer
can initiate them. Their primary use is for uploading and downloading
PLC-2 memory.