Methods of transmission -13, Methods of transmission – Rockwell Automation 2706-P42_P43_P44_P72_P74_P92_P94 InView Marquee Message Display User Manual User Manual

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Publication 2706-UM016D-EN-P - March 2006

InView Protocol 4-13

For example, when using priority messaging, messages are sent to
holding register 40103. The register number that is transmitted would
be (40103-40001=102) or 102 (0x66) would be transmitted at 100
(64h). The following shows the memory map for the displays.

Methods of Transmission

There are eight different methods of transmission of data to and from
the display. Each one of these use 1 of 4 different Modbus function
codes.

The table, Modbus Function Codes used in InView Products, explains
each of the four Modbus ASCII function codes used. The table,
Methods of Transportation, shows the eight methods of using these
codes with the product.

Memory Map

Modbus Holding Registers

Registers

Description

40001

001

Variables registers

Variables 001-100 (00-99 with automation
software)

40100

100

40101

101

Add a Message/Downloading of messages

40102

102

Remove a Message

40103

103

Message Queue/Priority Messaging

40167

167

Modbus Function Codes used in InView Products

Function
Code

Function
Code Hex

Modbus
Meaning

Action.

01

01

Read Coil status

Used to signal the downloading messages to the display.

03

03

Read Output
Registers Query

Used to read registers in a display.

06

06

Preset Single
Register

Used to preset a single register in a display (Priority Messaging, Update Variables, and
Add/Remove a Message).

16

10

Preset Multiple
Registers

Used to preset multiple registers in a display (Add/Remove a Message or Update
Variables).

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