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5.1.4
Exception Response
If an error occurs, the slave sends an exception response message to master consisting of
the slave address, function code, exception response code and error check field. In an
exception response, the slave sets the high-order bit (MSB) of the response function code
to one. The exception response codes are listed below.
Code
Name
Descriptions
01
Illegal Function
The message function received is not allowable
action.
02
Illegal Data Address
The address referenced in the data field is not valid.
03
Illegal Data Value
The value referenced at the addressed device
location is no within range.
04
Slave Device Failure
An unrecoverable error occurred while the slave
was attempting to perform the requested action.
05
Acknowledge
The slave has accepted the request and processing
it, but a long duration of time will be required to do
so.
06
Slave Device Busy
The slave is engaged in processing a long-duration
program command.
07
Negative Acknowledge
The slave cannot perform the program function
received in the query.
08
Memory Parity Error
The slave attempted to read extended memory, but
detected a parity error in the memory.
5.2 JetI/O 6510 Modbus/TCP Address Mapping
Note: Some of the results are using Hex (Ex: FF00H) mode, Signed (-1) mode... or others
mode. This result depends on the value of the address. There are two types Modbus/TCP
addresses. The protocol address is an address from 0000 to the last address of the function
code you choose. The PLC address is the fixed address number of the function code. This is
also defined in Modbus/TCP protocol. Please choose the type your application uses.
Should you encounter problem on reading this, please contact our technical support engineer,
JetI/O 6510 Common Register Map (Holding Registers, Function Code = 03)
Protocol
Address
(Hex)
PLC
Address
(Decimal)
Access
Description
0000
40001
R/
W
(Read/Write)
Host
Watch-dog
enable/disable
R/W:AABB
AABB:0000H (disable)
AABB:FF00H (enable)
0001
40002
R/W
(Read/Write) Host Watch-dog cycle
count