Rockwell Automation 2706-LV2P_LV2R_LV4P_LV4R DL40 PLUS USER MANUAL - Manual (Page 122)

Remote I/O Communications 8–30
Publication 2706-6.1
Adding or Deleting Messages using a Block Transfer Write
The following shows the format of a discrete I/O message trigger in
the Message List run mode. If Block Transfer Write Length is set to
0 in your PLC program, a default length of 2 is used.
WORD 1
17 16 15 14 Priority Message Number
Message Number
WORD 0
Add/Delete Bit
Block Transfer Write File
(Any rack size)
Messages can be added or deleted while priority messages are
triggered. To trigger a Priority Message without changing the
Message List, set the message number (in word 1) to 0.
Return Message Number and ASCII Data (Block Transfer Read)
The following shows the format of block transfer data returned to the
PLC in Message List run mode. This data may include both the
message number and message text. If Block Transfer Read Length is
set to 0 in the PLC program, the DL40 Plus returns 12 words.
WORD 1
17 16 15 14
Message Number
WORD 0
Enter Bit
Block Transfer Read File
Any rack size-2 to 12 Words
WORD 2
WORD 3
ASCII Character 1
Acknowledge Bit
Clock/Date Data Bit = 0
Diagnostic Code
ASCII Character 3
ASCII Character 2
ASCII Character 4
WORD 4
WORD 5 ASCII Character 7
ASCII Character 6
ASCII Character 8
ASCII Character 5
WORD 6
WORD 7 ASCII Character 11
ASCII Character 10
ASCII Character 12
ASCII Character 9
WORD 8 ASCII Character 13 ASCII Character 14
WORD 9 ASCII Character 15 ASCII Character 16
WORD 10 ASCII Character 17 ASCII Character 18
WORD 11 ASCII Character 19 ASCII Character 20
Length of Message List