Siemens S7 Memory Block Tag

Introduction

The Siemens S7 Memory Block Tag Register Block Tag Icon specifies a region of Siemens S7 PLC memory and how often to read the data from the PLC.

Configuration Properties

The Siemens S7 Memory Block Tag supports the configuration properties of the Byte Register Block Tag plus these properties:

Property Type Version Description
ScanInterval TIME 1.4 The interval between each read. See Interval and Offset for information on how timed activities are scheduled.
ScanOffset TIME 1.4 The offset added to the ScanInterval to get the actual read time. See Interval and Offset for information on how timed activities are scheduled.
PLC Reference 1.4 The Siemens S7 PLC Tag where the Memory Block is located.
MemoryAddress STRING 1.8 The memory address of the first byte of the register block.
See Siemens S7 PLC Data Address Format for information on how this field is formatted. Click the Browse button Browse button to access the memory address editor.
ByteCount UINT 1.4 The number of bytes to read from the PLC.

Tag Commands

The Siemens S7 Memory Block Tag supports these tag commands:

Tag Command Version Description
Refresh 1.4 Requests an immediate read of the data from the PLC.

Note: Event triggered data reads (from the Refresh tag command) and periodic data reads (defined by the ScanInterval property) are independent. You can use the Refresh tag command, or the ScanInterval property, or both to determine when the data is read from the PLC.

Relationships to Other Tag Types

The Siemens Memory Block Tag builds on the features of these tag types:

Further Information

Interval and Offset

To learn how activities are scheduled using Interval and Offset.

Siemens S7 PLC Data Address Format

To learn about how to specify a data location in a Siemens S7 PLC Tag.

IO Analog Data Tag

To learn about the IO Analog Data Tag that can be associated with the Siemens S7 Memory Block Tag.

IO Digital Data Tag

To learn about the IO Digital Data Tag that can be associated with the Siemens S7 Memory Block Tag.

IO String Data Tag

To learn about the IO String Data Tag that can be associated with the Siemens S7 Memory Block Tag.

IO Word Data Tag

To learn about the IO Word Data Tag that can be associated with the Siemens S7 Memory Block Tag.

IO Double Word Data Tag

To learn about the IO Double Word Data Tag that can be associated with the Siemens S7 Memory Block Tag.

Siemens S7 Driver

For an overview of the Siemens S7 Driver.

Byte Register Block Tag

To learn about properties common to all Byte Register Block Tags.

Glossary

For the meaning of terms used in Fernhill SCADA.