Serious Issue in Modbus Binding

[Hussain_Alahmed]

Hi,

i am using Modbus binding on Raspberry PI4 (Openhabian 3.0.2) with RS-485 to USB convertor , it work great with no issue but i have noticed sudden crash for Openhab quite often now which means openhab stop working or responding at all and USB stop communication to modbus salve devices .

finding :

1. when i have error in log for modbus RS-485 communication (via USB convertor) the crash happen and when i have more error the crash happen faster.
2. when crash happen openhab stop responding and logs are freezes while i still can access SSH and reboot Raspberry PI.

any help please

code:

UID: modbus:serial:156451a229
label: 2_Serial Slave Micro
thingTypeUID: modbus:serial
configuration:
  baud: 9600
  timeBetweenTransactionsMillis: 35
  connectMaxTries: 1
  stopBits: "1.0"
  parity: none
  receiveTimeoutMillis: 1500
  dataBits: 8
  echo: false
  encoding: rtu
  flowControlIn: none
  port: /dev/ttyUSB0
  flowControlOut: none
  connectTimeoutMillis: 10000
  id: 2
  enableDiscovery: false

UID: modbus:poller:156451a229:50f7d7d314
label: 2_ DO Poll
thingTypeUID: modbus:poller
configuration:
  start: 220
  length: 1
  refresh: 50
  maxTries: 3
  cacheMillis: 50
  type: coil
bridgeUID: modbus:serial:156451a229

UID: modbus:data:50f7d7d314:ce5fe50177
label: 2_DO 3
thingTypeUID: modbus:data
configuration:
  readTransform: default
  writeType: coil
  writeTransform: default
  updateUnchangedValuesEveryMillis: 1000
  writeValueType: bit
  writeMultipleEvenWithSingleRegisterOrCoil: false
  writeMaxTries: 3
  writeStart: "220"
bridgeUID: modbus:poller:156451a229:50f7d7d314

[rossko57]

Your screenshot doesn’t show any crash. It does show a WARN from the binding, that it had an error and is going to retry the transfer. This would be pretty routine stuff in itself for Modbus.

@Hussain_Alahmed

USB stop communication to modbus salve devices

This sounds like problems looked at in this long thread, essentially if you have a “routine” serial comms error, the recovery may go wrong.

Modbus Binding not working on OH3

FYI here, I’ve introduced a possible workaround for the serial library issues in modbus binding: [modbus] Workaround for nrjavaserial issues: do not disconnect serial by ssalonen · Pull Request #2272 · openhab/openhab-core · GitHub

Some work has been done, so you might want to move up to Milestone or Snapshot version to get that, or wait for 3.1 release due soon.

[Hussain_Alahmed]

@Modbus Binding not working on OH3

[modbus] Workaround for nrjavaserial issues: do not disconnect serial by ssalonen · Pull Request #2272 · openhab/openhab-core · GitHub

yes correct my screenshot does not till any thing about the crash and im not sure where to find the right logs because that all what i found and i’m not linux user to go deep in linux side

looks like the thread is about the same , thanks for sharing this will be helpful