Specifications

PA/4000 User’s Manual
Appendix C, PA/4000 Remote I/O
Page 8
Message Parameters for RIO
RIO Module drops null characters (ASCII \00).
A message can be up to 64 words or 128 ASCII characters long.
Messages of less than 64 words or 128 ASCII characters need to be padded with null
characters-ASCII \00. If null characters are omitted, transmission will not occur.
The RIO uses discrete transfer to send data back to the PLC-not block transfer.
Slot 8 of the first rack indicates data availability. If the data is not read for six seconds, it is
lost.
Sample Program for RIO
The diskette included with this system has a sample ladder logic program that
prints messages with a PA/4000. It can serve as a first step in establishing
successful communication between the PA/4000 and the PLC.
Equipment used to set up Sample Program
The listing below details a configuration verified by Diagraph that successfully ran
the Sample Program.
Software Allen-Bradley's software 6200, Release 5.0
PA/4000 Factory installed RIO
(EN)
(DN)
(ER)
BTW
BLOCK TRANSFER WRITE
Rack
Gr oup
Module
Control block
Data file
Length
Continuous
03
0
0
BT10:1
A12:0
64
N
BTW
BLOCK TRANSFER WRITE
Rack
Gr oup
Module
Control block
Data file
Length
Continuous
03
0
0
BT10:2
A12:100
64
N
BT10:1
] [
DN
(EN)
(DN)
(ER)
B3
] [
1
BT10:2
]/[
DN
Rung 1
BT10:2
] [
DN
B3
(U)
1
BT10:1
(U)
DN
BT10:2
(U)
DN
I:030
] [
10
BTR
BLOCK TRANSFER READ
Rack
Gr oup
Module
Control block
Data file
Length
Continuous
03
0
0
BT10:4
A12:200
64
N
(EN)
(DN)
(ER)
Rung 2
Rung 3
END OF FILE