Address Syntax

The new Syntax has the following motivation

• Be more familiar with the TIA Syntax well known by S7 programmers
• Add Type Information to support all available TIA types
• "Type inference" to be not too verbose

Supported types

Syntax

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Datablocks

Addressing is different for non-primitive and primitive types.

The general syntax for addressing primitive values in a Datablock is

%DB{db-number}.DB{bit-length-code}{byte-offset}(.{bit-offset})?

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db-number: number of datablock
bit-length-code:
	X - 1 bit
	B - 8 bit / 1 byte
	W - 16 bit / 2 byte
	D - 32 bit / 4 byte
byte-offset: offset in byte to start of data block
bit-offset: offset in bit to start of bit

For non primitive objects the (pointer?) notation from TIA is used which is

P#DB{db-number}.DBX{byte-offset}.{bit-offset}
Note, here, bit offset is not optional but usually always 0

The parts are:

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Type identifier Postfix

Primitives

Generally the TIA Syntax is used:

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SINT
USINT
DINT
LREAL
LINT
ULINTtax

Strings

Please see https://support.industry.siemens.com/tf/WW/en/posts/string-data-type/51621?page=0&pageSize=10

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%DB3.DX4.1
%DB3.DX4.1:BOOL
%DB3.DB4:INT
%DB3.DB4:UINT
%DB3.DW4:REAL

Special Data Areas: Markers, Inputs, Outputs

They are always adressed bit-wise and the syntax is similar to TIA.

// Marker
%M1.0 // byte 1, bit 0
%I0.5 // byte 0, bit 5
%Q1.1 // byte 1, bit 1

Additional Documents

Programming Guideline

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Direct Adressing Overview

http://www.multiprojekt.pl/ftp/weintek_hmi/plc_connection_guide/Siemens_S7_1200_S7_1500_absolute_addressing_Ethernet.pdf