# Modbus TCP device tags have "Bad" as value **URL:** \ **Category:** Ignition\ **Tags:** vision\ **Created:** [February 5, 2025, 2:14pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902 "2025-02-05T14:14:03Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Xabier\_Garcia](https://avatars.discourse-cdn.com/v4/letter/x/57b2e6/32.png) [@Xabier\_Garcia](https://forum.inductiveautomation.com/u/Xabier_Garcia)\ **Post date:** [February 5, 2025, 2:14pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/1 "2025-02-05T14:14:03Z")
I have 8 devices conected via modbus tcp and I can read tags correctly out of 7 of them with the same address structure. The one not working just sets the value to Bad ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/d/3dd63fbe36b92349562fb2edd10cb1b97594fd3c.png) Since they are all the same device I know that I am connecting propperly so the problem should be on this one speciffically. Yet when I check the IP outside of Ignition, the data shows fine. I tryed making a new device changing names, settings... doesn't work. Also the Gateway can't read the value, only returns null. ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [February 5, 2025, 2:16pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/2 "2025-02-05T14:16:57Z")
Show the rest of your tag properties, of the broken one and a working one. ---
**Author:** ![Xabier\_Garcia](https://avatars.discourse-cdn.com/v4/letter/x/57b2e6/32.png) [@Xabier\_Garcia](https://forum.inductiveautomation.com/u/Xabier_Garcia)\ **Post date:** [February 5, 2025, 2:19pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/3 "2025-02-05T14:19:59Z")
Here is for a working one: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/2/921ed27367d252321119b557565e00ee20b1fccd.png) Here one not working: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/b/ebaf1bb9732136d7ba51fdcbd92863b144a4a1d7.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 5, 2025, 2:33pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/4 "2025-02-05T14:33:54Z")
This OPC Item Path syntax means you've chosen to set up an "Address Map" on the driver. Does the device that isn't working have an address map set up and is it the same as the others? ---
**Author:** ![Xabier\_Garcia](https://avatars.discourse-cdn.com/v4/letter/x/57b2e6/32.png) [@Xabier\_Garcia](https://forum.inductiveautomation.com/u/Xabier_Garcia)\ **Post date:** [February 5, 2025, 2:40pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/5 "2025-02-05T14:40:56Z")
Yes, all have the same address map. Same devices showed before, first the working one: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/5/257c32afba91853b7b0a669aa46528b0cf1af30e.png) And the one not working: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/f/3f6df67cfd0f4d5f7d840c7b384ab66f97af5352.png) if I go to the Gateway: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/6/0/60c4743de98e4ca234324801fe3f6aecb2de4de9.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 5, 2025, 2:41pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/6 "2025-02-05T14:41:27Z")
Are there errors in the gateway logs from this device? Is zero-based addressing enabled for this device? ---
**Author:** ![Xabier\_Garcia](https://avatars.discourse-cdn.com/v4/letter/x/57b2e6/32.png) [@Xabier\_Garcia](https://forum.inductiveautomation.com/u/Xabier_Garcia)\ **Post date:** [February 5, 2025, 2:48pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/7 "2025-02-05T14:48:47Z")
the log only shows this: INFO | jvm 1 | 2025/02/05 15:45:55 | E [d.M.ReadInputRegistersRequest] [15:45:55.088]: Received response with ExceptionCode: 0x0B (GatewayTargetDeviceFailToRespond). unitId=1, startAddress=0, quantity=64 device-name=SS\_IBI1\_SOLA\_INVE1\_2 yes, zero-based addressing is enabled: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/b/1b8faec04ca777ccd22aa08d908ae4c7d6011a00.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 5, 2025, 3:12pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/8 "2025-02-05T15:12:47Z")
The Modbus gateway device you're communicating with is returning that ExceptionCode. There doesn't appear to be anything wrong on the Ignition side. > [@Xabier\_Garcia](#): > > ExceptionCode: 0x0B (GatewayTargetDeviceFailToRespond). unitId=1, startAddress=0, quantity=64 device-name=SS\_IBI1\_SOLA\_INVE1\_2 ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [February 5, 2025, 3:31pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/9 "2025-02-05T15:31:52Z")
Those two mappings are pointing at the same registers. Is that intended? (I'm not sure the driver can handle that.) Consider not using mappings. Just use items paths like `[device]1.IRUS0` through `[device]1.IRUS63`. ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [February 5, 2025, 3:32pm UTC](https://forum.inductiveautomation.com/t/modbus-tcp-device-tags-have-bad-as-value/101902/10 "2025-02-05T15:32:58Z")
I assumed those mappings were for separate devices / IP addresses, but if that's not the case, and they are pointing at the same gateway device, then yes they are.