Modbus timing and timeouts

francescoizzi · Post by **francescoizzi** » 14 Feb 2019, 09:38

Hi all,

i try to configure a revolutionPi3 to read RS485 High performance soil and subtrates moisture sensor but without success.

I configured the modbus rtu master in pictory as usual ... image below ...

: Schermata 2019-02-14 alle 09.18.20.png (334.54 KiB) Viewed 4257 times

the piTest always fail with 110 error:

piTest -r Modbus_Action_Status_1
1 Byte-Value of Modbus_Action_Status_1: 110 dez (=6e hex)
1 Byte-Value of Modbus_Action_Status_1: 110 dez (=6e hex)
1 Byte-Value of Modbus_Action_Status_1: 110 dez (=6e hex)
1 Byte-Value of Modbus_Action_Status_1: 110 dez (=6e hex)
1 Byte-Value of Modbus_Action_Status_1: 110 dez (=6e hex)

The strange thing is that with QmodBus installed on Raspberry i successful connect and read register... image below...

: Schermata 2019-02-14 alle 09.34.59.jpg (449.94 KiB) Viewed 4257 times

The register 15 is the sensor board temperature ... the read value is correct

Any suggestion ?

zhan · Post by **zhan** » 16 May 2019, 15:10

hi francescoizzi,

sorry for replying late.

https://revolution.kunbus.com/tutorials ... rect=en_US
in this document, the 110 is described as "CONNECTION TIMED OUT The slave did not respond fast enough or not at all. Check your configuration and wiring."
Maybe in your case it is just not fast enough, is it possible?

thanks.
Simon