Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 103)

Message Packet Formats
Chapter 5
5-24
Enable Scan
This command restarts the PLC processor’s program scanner after a
physical write operation has been performed. Note that you must always
use the enable scan command to restart the PLC processor after a physical
write command.
Command Format:
Reply Format:
TNS STS CMD
07
SRC DST
TNS STS CMD
47
SRC DST
FNC
03
Physical Read
This command reads bytes of data from the PC data table or program
memory. Use this command to upload the contents of PLC memory to
your computer.
Use the SIZE field to specify the number of bytes to be read. 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
04
SRC DST
TNS STS CMD
44
SRC DST
ADDR
DATA — Max. of 244 Bytes
SIZE