Function Codes; Exceptions And Error Responds; B.2.6 Function Codes - GE F650 Instruction Manual

B.2 MODBUS F650
CODE MODBUS
NAME
HEX DEC
03 3 Read Holding
Registers
B
04 4 Read Input
Registers
10 16 Preset Multiple
Registers
The following table shows error codes defined in ModBus protocol:
01 ILLEGAL FUNCTION
02 ILLEGAL DATA ADDRESS
03 ILLEGAL DATA VALUE
04 ILLEGAL RESPONSE LENGTH Indicates that a response to the master's request would exceed the maximum specified size for
05 ACKNOWLEDGE
06 SLAVE DEVICE BUSY
07 NEGATIVE ACKNOWLEDGE
B-6
F650 COMMENT
DEFINITION
Reading of any Any of these two functions allow the master to read 1 or more consecutive relay
value addresses. Registers are always 16-bit long with the most important byte first. The
maximum number of registers that can be read in a single package is 125, equivalent
Reading of any
to 250 bytes.
value
Writing This function allows writing 1 or more registers representing one or more settings.
Registers are 2-byte long values, transmitted with the most important byte first. The
maximum number of registers to be written in a single package is 125.
The slave does not support any function with the received function code in this message.
Master is trying to perform an operation in an incorrect address.
Slave has detected that the value sent by the master is not valid.
that function code.
Generic acknowledgement.
Slave is busy and cannot perform the requested operation.
Negative acknowledgement.
F650 Digital Bay Controller

B.2.6 FUNCTION CODES

B.2.7 EXCEPTIONS AND ERROR RESPONDS
APPENDIX B
GEK-106310AB