Unable to move emonTx5 to node 28

I have newly acquired emonTx5. By default, this uses node 27, but I already have an additional emonTH on that address.

According to the documentation, the address can be changed to 28 using the switch on the board. Comparing the switch on my board and the switch in the website images, it appears to have had the plastic rotor chopped off and it doesn’t turn. It does push, but this seems to make no difference.

According (again) to the firmware, I can change the node to be 28 using a terminal session. I’ve attached the output from such a session and it can be seen that the firmware acknowledges the change, but no change in the transmitted data occurs. I tried ‘s’ and ‘x’ to save and lock the new config, but after a power cycle, it’s still on node 27. Incidentally, none of the commands other than ‘n’ respond with any output and seem to have no effect. ‘?’ produces nothing.

My board has no connector on the FTDI connection, so I can’t even burn new firmware without getting out the soldering iron - which would probably void the warranty.

So, how do I change this to use node 28?

Hi @Guff666

Looking at the source and the board, this switch is only present on the emonTx4, not the 5.

This suggests you might have your line terminations “wrong”. Do you know if you’re sending \r\n or just \n? Which serial terminal are you using?

I’m sending \r\n. n to change nodeRf works OK.

@Guff666

A bit of a repeat of what @awjlogan said above, but it may be useful …

The emonTx5 uses the board from the emonPi2. I think the address ‘switch’ you are referring to is the display scroll button from the emonPi2. I don’t think it’s used in the emonTx5 as the emonTx5 doesn’t have a display.

The emonTx5 design is roughly similar to the emonTx4, although the emonTx5 doesn’t have the address select DIP switch of the emonTx4. So I guess the address needs to be configured over the USB port. I wrote some notes on configuring the emonTx4 over USB which may be useful. See

N.B. the emonTx4 cofiguration can also be updated using the web tool, but I don’t know if there is a version for the emonTx5? It doesn’t seem to be mentioned in the emonTx5 docs. See …

Good luck!

EDIT - @Guff666 it seems that you may have fixed this while I was writing my reply? - that’s good.

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Try configuring to just use \n - you said that single inputs like ? don’t work and looking at the code, it does not appear to handle \r\n. For example, if you were to send ?\r\n, len would be 2 rather than 1 and the condition would fail. This would mean that when you are trying to do s to save, it is not registering.

Relevant line in the code here.

There is no check for the len value for the n option, and the atoi function will silently swallow the trailing \r.

This is exactly the same thing @rupert has written about in his linked post.

That’s solved it @awjlogan Angus. Telling the terminal to send only \n allowed me to save the config.

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