Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command User Manual
Page 230
13–15
PLC Addressing
Publication 1770Ć6.5.16 - October 1996
PLCĆ5/250 RM/LP Memory (for use with figures on page 13-14)
level 1
level 2
level 3
level 4
level 5
level 6
level 7
1 public stat word
2 data
0 system
sect
file
element
member
submember
0 binary
1 integer
2 long integer
3 reserved
4 float
5 timer
0 EN
1 TT
2 DN
3 PRE
4 ACC
6 counter
0 CU
1 CD
2 DN
3 OV
4 UN
5 PRE
6 ACC
7 control
8 PID
9 message
10 string
Logical ASCII Addressing
Logical ASCII addressing is supported by PLC-5/250, PLC-5, and
PLC-3 processors. Logical ASCII addressing allows you to specify
an address in the same form that you use at the programming node,
and lets any device communicate with any other device—without
knowing the internal memory structure of the target device.
A logical ASCII address starts with an ASCII NULL (0) character
and a dollar sign ($) to differentiate it from symbolic addressing.
The rest of the address then follows, as a string of ASCII characters.
The string is terminated with another NULL character.
Logical ASCII address that accesses the 360th element in file 10
Byte
ASCII HEX
Contents
1
NUL
0 0
A null character that tells the PLCĆ5 processor that an ASCII
address is to follow.
2
$
2 4
An ASCII $" that differentiates a logical ASCII address from a
symbolic address.
3
N
4 E
A hex value that corresponds to one character in the PLCĆ5
4
1
3 1
p
ASCII address N10:360. Each byte contains a hex value.
For example byte 3 contains the value for the ASCII character
5
0
3 0
For example, byte 3 contains the value for the ASCII character
(4 E). Refer to Chapter 15, ASCII Codes," for a list of ASCII
6
:
3 A
(4 E). Refer to Chapter 15, ASCII Codes," for a list of ASCII
characters and their hex, binary, and decimal values.
7
3
3 3
characters and their hex, binary, and decimal values.
8
6
3 6
9
0
3 0
10
NUL
0 0
A null character that ends the ASCII address specification.