Arduino IDE can only program chip, not read its program memory. But you can use AVRDUDE ( maybe with some GUI ) for reading program memory from your chip. And in your program sketch define some string to identify version. It can be read hex output of program memory then.

You seem to send the temp messages under a different ChildID than it is presented: presentation takes "1", send uses "0". You have to allign that, e.g. by using send(msg.setSensor(i+CHILD_ID_TEMP).set(temperature,1)); But as long as there's just one DS18B20 doing that dynamically doesn't really make sense. Using the defined message structure (MyMessage msgTemp...) could make things more transparent. Also there's no sending command for voltage. So why do you expect the controller to receive also voltage?

@gohan Ok will try that see if I made a fault somewhere

Just use any mqtt client and subscribe to topic # , you will be able to see all messages and pick the one you are looking for

Any ideas on this any one? How to troubleshoot this? Would be nice to get this working. Thanks W.