Modbus Register / T3-Nano Issue

Hi Maurice,
Would you be able to assist with this or point me towards your best guys for the answer please.

I’m trying to read an input register on a modbus TCP device with ethernet IP ending .173, it is using port 502 as standard and I’m trying to read register 3022 however when I refresh the program code after sending to to the T3-Nano (non-ESP32 version) fw 63.2 it changes to something different:

this is my coding which I enter:
120 PV1VOLT = 173MB_INPUTREG3022

which changes to this after a refresh:

Is this something I am doing wrong? can I do it differently? or is it a limitation on the register number?

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I believe I may have found the issue, in your T3000_Bacnet_Programmable_Controller_Series document it mentions “2.4.REGx to read and write remote modbus points. MB_REG is base 0, and REG is base1.Range of x is 0 to 2047.”

Would I be correct that this still stands? if so it’s a problem, does the ESP32 version have the same limitation? Is it possible for a FW upgrade to allow a larger range?

Thanks for any support you can offer

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Current T3000 only support MB_REGXX to 65535, we will fix it in next version soon. we will response you once we release new T3000.exe.

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Hi Chelsea,
Thanks for your reply, just so there is no confusion, it is in the T3-Nano I need to read the high register numbers, the values can then be placed in Vars for manipulation.

Out of interest, does the ESP32 version have the same restriction?



basic function is same.

Hi Chelsea,
I notice that the nano has been lifted to revision 63.6 and also T3000 has been updated, but still have the same issue, would it be that this issue has not been fixed yet?

we uploaded T3000.exe last Firday, can you confirm it the version of T3000? The demo code i showed is register 3022. I sent the program and read it back, it comes back correctly as 3022. If you were to use the older T3000 it will not read back correctly but the latest one is OK.

Thanks Chelsea,
That’s great progress thank you, I guess I must have updated before your update.

So still have an issue, not sure if it is a limitation or my syntax of the programming:
This is the code:

This is the Variable tables:

This is the result on the Network point:

Hardware wise the T3 is trying to read registers on a device (address 1) that is RS485 connected to an Elfin-EW11 RS485 to WiFi converter.
I have tried using the syntax 120 VAR25 = 173.1MB_INPUTREG3020 however that just greyed out.

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