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1794-ie8h calibration command structure, 1794-ie8h calibration command structure -3 – Rockwell Automation 1794-OE8H FLEX I/O HART Analog Modules User Manual User Manual

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Publication 1794-UM063A-EN-P - March 2006

Calibrate Your Module 5-3

1794-IE8H Calibration
Command Structure

Calibration of the HART I/O module is performed using data structures and
MSG Ladder-logic instructions. The MSG instruction sends the data structure
to a dedicated attribute in the FLEX HART I/O module and the associated
response is read from the same attribute. The data structure contains
commands and its associated parameters. Depending on the command, they
are either writable or readable. Only one access, either read or write, is
executable at a time.

The Calibration data structure has four members: Command, Item, Data1, and
Data2.

Table 5.2 Calibration Data Structure

Attribute

Field Size

Implementation

Description

Value (Hex)

Access

67

hex

4 byte

struct {

Conditional

Read or write

USINT Command;

Calibration command;

USINT Item;

Additional command
information;

USINT Data1;

Data according to command;

USINT Data2;

Data according to command

} Calibration;

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