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Function 5: writing a bit, Function 6: writing a word, J-bus/modbus protocol – Rice Lake PR5230 Fieldbus Transmitter User Manual

Page 172: Pr 5230 instrument manual

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J-Bus/ModBus Protocol

PR 5230 Instrument Manual

EN-172

Sartorius

Function 5: Writing a Bit

Command

Device
address

Function
number

Address of
the bit

Value of
the bit

Always 0

1 byte

1 byte

2 bytes

1 byte

1 byte

Range

0...127

5

0...127

0 or 255

0


Reply

Device
address

Function
number

Address of
the bit

Value of
the bit

Always 0

1 byte

1 byte

2 bytes

1 byte

1 byte

If the address of the bit is out of the permissible range (0...127), an error message is sent as a reply.
Example of function 5 for setting bit 113 (taring) with ModBus-RTU:
Command

1

5

0

113

255

0

CRC

CRC

Reply

1

5

0

113

255

0

CRC

CRC

Example with ModBus-TCP:
Command

47

13

0

0

0

6

0

5

0

113

255

0

Reply

47

13

0

0

0

6

0

5

0

113

255

The individual bytes are shown.

Function 6: Writing a Word

Command

Device address Function

number

Word address Value of the

word

1 byte

1 byte

2 bytes

2 bytes

Range

0...127

6

0...63


Reply

Device address Function

number

Word address Value of the

word

1 byte

1 byte

2 bytes

2 bytes

If the address is out of the permissible range (0...63), an error message is sent as a reply.