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modbus discovery and address assignment
Posted: 08 Jul 2020, 01:32
by jobijobi
hi,
any implementations avail on doing rs485 discovery and address 'conflict resolution' to avoid having to hard-code an ID into each device.
thx
Re: modbus discovery and address assignment
Posted: 09 Jul 2020, 10:30
by dirk
Hi jobijobi, I have understood that you are want to use ModbusRTU. And you want to use Slave auto addressing to avoid selecting the slave addresses manually, right? This is a feature which is not implemented (yet).
Coud you be so kind to explain your application and your needs a bit more detailled?
Re: modbus discovery and address assignment
Posted: 21 Jul 2020, 17:30
by jobijobi
With 'PiCtory', you can be both master or slave.
If you happen to run two slaves with on the same bus, with same address, how is this handled today?
My idea was that we could have a graceful error-handling to resolve duplicate address conflicts.
It would be enough with the error-handling, then it's up to the application to expose a way to set a new address to the conflicting slave-device
Re: modbus discovery and address assignment
Posted: 22 Jul 2020, 14:14
by Amar
Modbus addressing is primitive. Engineer designing the host is also responsible for assigning all slave addresses to fit in with his/her overall system design. If N slaves are used and one of them has a duplicate address then error for configured slave ID (piCtory Extended Data for Modbus Master ) can also be found in system log and also by monitoring action_status_register.
tail -f /var/log/daemon.log