Issue specifying <object_type>+<start_address> about modpoll HOT 2 CLOSED

@digispiders Firstly, congratulate you have actually retrieved data according to your last screenshot.

As you mentioned, instead of polling start from the standard holding_register address 40001,

poll,holding_register,40001,10,BE_BE
ref,objectname,40001,uint16,r

you end up with polling start from address 1,

poll,holding_register,1,10,BE_BE
ref,objectname,1,uint16,r

This happens quite often because Modbus is an open protocol, different vendors have their own interpretation on the standard, that's why we have many different variants, e.g. zero-based vs one-based, big-endian vs small-endian, etc. Usually vendors will provide documents/examples to help developers for integration.

In your case, your device vendor is using relative address (offset address) rather than absolute address for data comm.

Hope that helps for clarification.

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Okay. It was a little unclear to me based on the documentation in modpoll + what the manufacturer put out, in combination with my poor understanding of modbus addresses. I assumed that an address was an address, and if an 'offset' to an 'address' was specified (e.g. 1 to 40001), I should call the address (40002) which was probably wrong to assume. Feel to close.

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