Siemens Address Syntax

Open Automation Software Tags can be defined to connect directly to Siemens controllers with the built in Siemens Driver Interfaces which support communications over Ethernet to S7-200, S7-300, S7-400, S7-1200, and S7-1500.

The following steps can be used to setup direct communications with Siemens controllers:

Syntax

Standard Types:

<Memory Area><Data Width><Address>
<Memory Area><Data Width><Address>.<Bit>

S7-200 Timer and Counter:

<Memory Type><Address>

Data Block:

DB<Number>.DB<Data Width><Address>
DB<Number>.DB<Data Width><Address>.<Bit>

Memory Areas

Memory Area	Description	Bit Access	Byte Access	Word Access	DWord Access
I, E	Discrete Inputs and Image Register	R/W	R/W	R/W	R/W
Q, A	Discrete Outputs and Image Register	R/W	R/W	R/W	R/W
M	Internal Memory Bits	R/W	R/W	R/W	R/W
SM	Special memory Bits	R/W	R/W	R/W	R/W
V	Variable Memory	R/W	R/W	R/W	R/W
T	Timer Current and Timer Bit	R/W (T.Bit)	no	T.Current R/W	no
C	Counter Current and Counter Bit	R/W (C.Bit)	no	C.Current R/W	no
HC	High-speed Counter	no	no	no	RO
AI	Analog Inputs	no	no	RO	no
AQ	Analog Outputs	no	no	RW	no
AC	Accumulator	no	no	no	no
L	Local Variable Memory	no	no	no	no
S	SCR	R/W	R/W	R/W	R/W

S7-300, S7-400

Memory Area	Description	Bit Access	Byte Access	Word Access	DWord Access
I, E	Discrete Inputs and Image Register	R/W	R/W	R/W	R/W
Q, A	Discrete Outputs and Image Register	R/W	R/W	R/W	R/W
M, F	Internal Memory Bits	R/W	R/W	R/W	R/W
PI, PE	Peripheral Inputs	R/W	R/W	R/W	R/W
PQ, PA	Peripheral Outputs	R/W	R/W	R/W	R/W
DB	Datablock Memory	R/W	R/W	R/W	R/W

 

S7-1200, S7-1500

Memory Area	Description	Bit Access	Byte Access	Word Access	DWord Access
I, E	Discrete Inputs and Image Register	R/W	R/W	R/W	R/W
Q, A	Discrete Outputs and Image Register	R/W	R/W	R/W	R/W
M, F	Internal Memory Bits	R/W	R/W	R/W	R/W
DB	Datablock Memory	R/W	R/W	R/W	R/W

 

Data Width

Data Width Specifier	Description	Bits	Supported Data Types
X, none	Bit	1	Boolean
B	Byte	8	SByte, Byte, BCD8, String, Structured Types
W	Word	16	Int16, UInt16, BCD16, WString
D	DWord	32	Int32, UInt32, BCD32, Single

 

Address

Address is controller family and model dependent. Consult controller documentation for valid ranges.

Bit

Data Width Specifier	Description	Valid Range
B	Byte	0..7
W	Word	0..15
D	DWord	0..31

Note: If error code 0x00000005 – Address does not exist or is out of range is returned as a system error uncheck Optimized block access attribute of dbOptimized in the controller program and re-compile and upload to the controller.