User Guide
Table Of Contents
- 1. Safety
- 2. Modbus - general info
- 3. Modbus technical data
- 4. Modbus installation
- 5. Programming
- 5.2.1 Ethernet common settings (M5.8.1)
- 5.2.2 Modbus TCP settings (M5.8.2)
- 5.3.1 Modbus RTU Parameters
- 5.3.2 Modbus RTU monitoring values
- 5.4.1 Ethernet common settings
- 5.4.2 Modbus TCP settings
- 5.4.2.1 Common settings
- 5.4.3 Modbus TCP monitoring values
- 5.4.3.1 Connection 1
- 5.4.3.2 Connection 2
- 6.3.1 Coil registers
- 6.3.2 Input discrete registers
- 6.3.3 Holding and input registers
- 6.3.3.1 Drive Application ID’s
- 6.3.3.2 FB Process data IN
- 6.3.3.3 FB Process data OUT
- 6.3.3.4 ID map
- 6.3.3.5 Operation day counter
- 6.3.3.6 Resettable operation day counter
- 6.3.3.7 Energy counter
- 6.3.3.8 Resettable energy counter
- 6.3.3.9 Fault history
Communications Honeywell • 33
Example of an exception response
In an exception response, the Slave sets the most-significant bit (MSB) of the function code to
1. The Slave returns an exception code in the data field.
Command Master - Slave:
Message frame:
Exception response:
Answer Slave - Master:
Reply frame:
ADDRESS 01 hex Slave address 1 hex (= 1)
FUNCTION 04 hex Function 4 hex (= 4)
DATA Starting address HI 17 hex Starting address 1770 hex (= 6000)
Starting address LO 70 hex
No. of registers HI 00 hex Invalid number of registers 0005 hex (= 5)
No. of registers LO 05 hex
ERROR CRC HI 34 hex
CHECK CRC LO 66 hex CRC field 3466 hex (=13414)
01 04 17 70 00 05 34 66
ADDRESS 01 hex Slave address 1 hex (= 1)
FUNCTION 84 hex Most significant bit set to 1
ERROR CODE 04 hex Error code 04 => Slave Device Failure
ERROR CRC HI 42 hex CRC field 42C3 hex (= 17091)
CHECK CRC LO C3 hex
01 84 04 42 C3