Message operation, Example – Rockwell Automation 1203 Serial Communications Module Series B User Manual

Page 57

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5–9

Block Transfer Emulation Instructions

1203–5.5 September 1995

Message Structure (Continued)

Data

Word 15

Data

Word 16

File, Group, Element

Minimum Value

Drive Response

Data

Word 17

Data

Word 18

Maximum Value

Default Value

Data

Word 19

Unit Text

Char 2

Char 1

Data

Word 20

Unit Text

Char 4

Char 3

Message Operation

Parameter Read Full retrieves the attributes of the specified
parameter. The attributes for each parameter include the data,
minimum and maximum values, and the parameter text. The
response message returns this information.

If an error has occurred in reading any of the values, word 1 contains
the status word.

The parameter text is returned with each data word containing two
ASCII characters per word. The first and second characters are in
opposite order.

Example

In this example, a Parameter Read Full was performed through block
transfer on a 1336 PLUS. N10:10 shows the header message for the
request. The data is returned in the response data file, starting with
word 1, for parameter 20. Word 1 shows the present value in drive
units. Word 2 through word 6 provide scaling information, used to
convert drive units to engineering units for the Human Interface
Module (HIM). Word 7 through word 14 provide the parameter
name.

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