Modbus Exception Codes; Table 16: Exception Codes - ABB GW100 User Manual

TR OUB LESHOOT IN G
Problem
Device is stuck in handshak-
ing state
Error Retrieving AP Mote
Data From Network Manager
Network Manager Has Reset. Wait for System Recovery to automatically initiate system recovery. It is of-
8.3

Modbus Exception Codes

The following exception codes are supported.
Exception code
0x01 ILLEGAL_FUNCTION
0x02 ILLEGAL_DATA_ADDRESS
0x03 ILLEGAL_DATA_VALUE
0x06 SLAVE DEVICE BUSY
0x0b GATEWAY TARGET DEVICE
FAILED TO RESPOND
3B NP 10299 2 B
Solution
Reboot the device stuck in handshaking state. If not possible, then reform
network or power cycle the gateway.
Note: Power cycling the gateway or reforming the network will force all de-
vices to drop off the network and reconnect. This will impact network
availability.
Wait for System Recovery to automatically initiate system recovery. It is of-
ten seen during the boot up process. If this error is persistent after 10+
minutes of boot up then a power cycle may be required.
ten seen during the boot up process or during network configuration. If
this error is persistent after 10+ minutes of boot up then a power cycle
may be required.

Table 16: Exception codes

Meaning
No request bytes present.
Starting address does not exist in mapping.
Starting register valid, but length of requests spans at least one un-
mapped register.
WirelessHART device is disconnected in simplified in mapping.
Slave is engaged in processing another command. Retry later.
This can happen when:
– The data is stale. This can be either because the data is old, or be-
cause the device is responding with a non-successful response
code.
– There is an update to the Modbus mapping in progress.
Indicates that no response was obtained from the target device.
This can happen when:
– Device is disconnected.
– Sending request to WirelessHART network failed.
To avoid Modbus exception notification, read each individual device data inde-
pendently. In a case of device disconnection, if you try to read data from multi-
ple devices in one block read, it will result in complete Modbus block read error.
M OD BUS EX CEPT IO N CODES
5 5