Request ibaPDA - > Modbus Server

Offs

Bytes

Type

Modbus Description

Contents(hex)

ibaPDA Description

MBAP

00

2

UINT

Transaction Identifier

xx xx

Incremented automatically in each circle

02

2

UINT

Protocol Identifier

00 00

0

04

2

UINT

Cmd Length

xx xx

nBytes + 7

06

1

BYTE

Unit Identifier

xx

Modbus server number

Fcode

07

1

BYTE

Function code

xx

0F: Write Multiple Coils 10: Write Multiple Registers

Data

08

2

UINT

Starting Address

xx xx

1. Address

10

2

UINT

Number of Values

xx xx

Number of the Coils or Holding Registers

12

1

BYTE

Number of Bytes

xx

13

n

BYTE

Data

xx xx

Output Values

Response Modbus -> Server ibaPDA

Offs

Bytes

Type

Modbus Description

Contents(hex)

ibaPDA Description

MBAP

00

2

UINT

Transaction Identifier

xx xx

Mirror of request

02

2

UINT

Protocol Identifier

00 00

0

04

2

UINT

Cmd Length

00 06

06

1

BYTE

Unit Identifier

xx

Mirror of request

Fcode

07

1

BYTE

Function code

xx

Mirror of request

Data

08

2

UINT

Starting Address

xx xx

Mirror of request

09

4

UINT

Number of values

xx xx

Mirror of request

Examples

Function 0F: Write Multiple Coils

Request

(hex)

(hex)

Response

Transaction Identifier

00 05

00 05

Transaction Identifier

Protocol Identifier

00 00

00 00

Protocol Identifier

Cmd LEN

00 09

00 06

Cmd LEN

Unit Identifier

01

01

Unit Identifier

FCode

0F

0F

FCode

Start Adr (Hi)

00

00

Start Adr (Hi)

Start Adr (Lo)

03

00

Start Adr (Lo)

No. Values (Hi)

00

00

No. Values (Hi)

No. Values (Lo)

0A

03

No. Values (Lo)

No. Bytes

02

Coils 11-8

xx

Coils 13-12

xx

Function 10: Write Multiple Registers

Request

(hex)

(hex)

Response

Transaction Identifier

00 06

00 06

Transaction Identifier

Protocol Identifier

00 00

00 00

Protocol Identifier

Cmd LEN

00 13

00 06

Cmd LEN

Unit Identifier

02

02

Unit Identifier

FCode

10

10

FCode

Start Adr (Hi)

00

00

Start Adr (Hi)

Start Adr (Lo)

20

20

Start Adr (Lo)

No. Values (Hi)

00

00

No. Values (Hi)

No. Values (Lo)

06

06

No. Values (Lo)

No. Bytes

0C

Register 33

xx xx

Register 34

xx xx

Register 35

xx xx

Register 36

xx xx

Register 37

xx xx

Register 38

xx xx