Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command - Manual (Page 100)

7–13 Communication Commands
Publication 1770Ć6.5.16 - October 1996
open file
Opens a file in an SLC 500 processor. If the file is successfully
opened, a Tag (low byte, high byte) is returned.
STS
FNC
81
CMD
0F
TNS DST SRC
STS
CMD
4F
SRC DST
Protection
File
number
C
R
File
type
TNS
Tag is used to access the open file using a protected type file read or protected type
file write. Tag is also used to close the file. The Tag field may be replaced by an
EXT STS field if there is an error.
Protection - 01h = read
02h = not supported
03h = read/write
Tag
physical read
Uploads data from the PLC data table or program memory.
1774-PLC and PLC-2
C
CMD
04 STS
TNS ADDR SIZE
R STS TNS
CMD
44
Data (max. 244 bytes)
DST SRC
SRC DST
Use the SIZE field to specify the number of bytes to be read. To specify a number of
PLC words, SIZE should be an even value because PLC words are two bytes.
PLC-3
For PLC-3 processors, the destination interface module accepts this
command only after the source node has successfully transmitted a
shutdown request.
CMD
0F
STS
FNC
09
TNS C
CMD
4F STS
TNS R
The EXT STS field may replace the DATA field if there is an error.
PLCĆ3 phys. address Size
TNS
Data (max. 244 bytes
or 122 words)
DST SRC
SRC DST
This command must request an even number of bytes.
• SLC 500
• SLC 5/03
• SLC 5/04
• 1774ĆPLC
• PLCĆ2
• PLCĆ3