Elliott flow computer address descriptions – Rockwell Automation 2711P Creating Modbus Applications User Manual

Page 82

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Publication 2711P-UM002B-EN-P - March 2007

82 Modbus (RTU) Serial Address Definitions

Elliott Flow Computer
Address Descriptions

Default data types for dynamically defined tags are shown in bold
where appropriate.

Important Notes

• Address ranges 405001 to 405315 and 407001 to 407315 are 32

bit registers. Addresses in the range of 405001 to 405315 use a
default data type of Long. Addresses in the range of 407001 to
407315 use a default data type of Float. Since these address
registers are 32 bit, only Float, DWord, Long or LBCD data types
are allowed. Arrays are not allowed for these special address
ranges.

• Arrays are supported for internal and holding register locations

(see note 1 above for exceptions) for all data types except
Boolean. There are two methods of addressing an array.
Examples are given using holding register locations.

4xxxx [rows] [cols]
4xxxx [cols] (this method assumes rows is equal to one)

• Rows multiplied by cols cannot exceed the block size that has

been assigned to the device for the register type. For arrays of 32
bit data types, rows multiplied by cols multiplied by 2 cannot
exceed the block size.

Elliott Flow Computer Addressing

Address

Range

Data Type

Access

Output Coils

000001 - 065536

Boolean

Read-Write

Input Coils

100001 - 165536

Boolean

Read Only

Internal Registers

300001 - 365536
300001 - 365535
3xxxxx.0 - 3xxxxx.15

Word, Short, Boolean
Float, DWord, Long, LBCD
Boolean

Read Only

Holding Registers

400001 - 465536
400001 - 465535
4xxxxx.0 - 4xxxxx.15

Word, Short, BCD (1)
Float, DWord, Long, LBCD,
Boolean

Read-Write

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