Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command - Manual (Page 95)

7–8 Communication Commands
Publication 1770Ć6.5.16 - October 1996
download request (download privilege)
Used by a computer to inform an interface module that it wants to
perform a download. If the module grants the download privilege,
the computer may begin issuing physical reads or physical writes.
If another node already has the download privilege, the second node
is denied the privilege.
Before performing an upload/download, issue diagnostic status to
get the last word of memory to read or write. Bytes 11-14 in the
diagnostic status reply return E60.0.0—this is the start of unused
memory. Start your read or write at 00 00 00 00.
CMD
0F
STS
FNC
05
TNS C
CMD
4F
STS TNS R
EXT
STS
DST SRC
SRC DST
The EXT STS field may be attached to the reply packet only when there is an error.
echo
Checks the integrity of transmissions over the communication link.
The command message transmits up to 243 bytes of data to a node
interface module. The receiving module should reply to this
command by transmitting the same data back to the originating node.
CMD
06 STS
FNC
00
Data (max. 243 bytes) TNS C
CMD
46 STS
Data (max. 243 bytes) TNS R
DST SRC
SRC DST
For SLC 500, SLC 5/01, and SLC 5/02 processors, maximum data
size is 95 bytes; for SLC 5/03 and SLC 5/04 processors, maximum
data size is 236 bytes.
• PLCĆ3
• 1774ĆPLC
• MicroLogix 1000
• PLCĆ2
• PLCĆ3
• PLCĆ5
• PLCĆ5/250
(receive only)
• SLC 500
• SLC 5/03
• SLC 5/04