I wanted to read the ZIV 5CTM smart meter that my electricity company provided at home to have good measurement on import and export of electricity.

The manual (ZIV - Monofásico 5CTM.pdf) says that its Optical port (Infrared) has these parameters:

• Optical port: as norm UNE EN 62056-21
• Signals: RX/TX
• Speed: 9600 baud
• ... trough the communication ports ... with the protocol DLMS/COSEM

From Gurux forums (post1, post2) I learnt these extra information:

• DLMS protocol over HDLC interface
• 9600 baud, 8N1
• Client: 2
• Server: 144 = 0x90
• Password for Low authentication (ASCII string): 00000001

I tested the gurux python client example with a Raspberry Pi with a TTL 3.3V serial IR port and it worked.

Then I decided to learn how to bring that into esphome.

external_components:
  - source: github:https://viric/esphome-ziv@master
    components: [ ziv ]

uart:
  id: mbus
  tx_pin: GPIO18
  rx_pin: GPIO19
  baud_rate: 9600
  data_bits: 8
  parity: NONE
  stop_bits: 1
  #debug:
  #  direction: BOTH
  #  after:
  #    delimiter: [ 0x7e ]

sensor:
  - platform: ziv
    update_interval: 60s
    import_active_energy:
      name: "Import active energy"
    export_active_energy:
      name: "Export active energy"
    import_active_power:
      name: "Import active power"
    export_active_power:
      name: "Export active power"

The code can be probably made to accomodate any other DLMS/HDLC/COSEM electricity meter, by changing the connection parameters currently hardcoded. But I don't have evidence of any other meter working like this, so I can't be sure.

For example, maybe it can be made to work with meters that use IEC 62056-21 mode E, currently not supported by this Aquaticus esphome module. It should be easy to change the initialisation parameters in src;

    esphome-ziv: esphome module for Ziv 5CTM electricity meters
    Copyright (C) 2023  Lluís Batlle i Rossell

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
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