[Help] Landis+Gyr E360-3P (ORES Wallonia Belgium) P1 port - ESPHome ESP32-C6 - Header found but telegram never parsed

ESPHome
1

Hardware:

  • Smart meter: Landis+Gyr E360-3P (triphasé / 3-phase)
  • Grid operator: ORES (Wallonia, Belgium)
  • P1 port: activated by ORES (paid activation)
  • Microcontroller: Waveshare ESP32-C6 Zero
  • Cable: standard straight RJ12 cable
  • RTS/Pin2: bridged directly to +5V (Pin1) on RJ12 connector
  • RX signal: Pin5 of RJ12 → GPIO2 of ESP32-C6 (with inverted: true)
  • Power: ESP32 powered via USB (not from P1 port)
  • ESPHome version: 2026.3.1

What works:
ESP32 boots, connects to WiFi :white_check_mark:
GPIO14 outputs 3.3V (RTS confirmed active) :white_check_mark:
Signal received on GPIO2 (confirmed with multimeter) :white_check_mark:
DSMR component finds the telegram header (/) every second :white_check_mark:

Problem:
The telegram header is found but the telegram is never fully parsed. No sensor values appear in Home Assistant — all remain unknown.
The only moment it was found is when i used the 7N2:

uart:
  id: uart_bus
  rx_pin:
    number: GPIO2
    inverted: true
    mode:
      input: true
      pullup: true
  baud_rate: 115200
  data_bits: 7
  parity: NONE
  stop_bits: 2
  rx_buffer_size: 4096

But the norm says it is a 8n1 (DSMR 5B) so i’m a bit lost.

Logs:

[V][dsmr:155]: Header of telegram found
[V][dsmr:155]: Header of telegram found
[V][dsmr:155]: Header of telegram found

…repeating every second, no parse, no values.
With dsmr_custom external component, got this error before increasing buffer:

With dsmr_custom external component, got this error before increasing buffer:
[E][dsmr_custom:346]: Error: Plain telegram larger than buffer (1500 bytes). Discarding.
This suggests the telegram from this meter is larger than 1500 bytes.

Current YAML:

uart:
  id: uart_bus
  rx_pin:
    number: GPIO2
    inverted: true
    mode:
      input: true
      pullup: true
  baud_rate: 115200
  data_bits: 8
  parity: NONE
  stop_bits: 1
  rx_buffer_size: 4096

dsmr:
  uart_id: uart_bus
  receive_timeout: 500ms
  crc_check: false
  max_telegram_length: 4096

Things already tried:

  • Multiple UART configs: 115200 8N1, 9600 7E1, 9600 7E2, 8E1 — both inverted and non-inverted
  • receive_timeout from 200ms to 5000ms
  • max_telegram_length up to 4096
  • rx_buffer_size up to 4096
  • crc_check: false
  • dsmr_custom external component
  • Pull-up enabled/disabled

Question:
Has anyone successfully read P1 data from a Landis+Gyr E360-3P with ORES in Wallonia using ESPHome? What is the correct UART configuration and are there any known quirks with this meter?
The meter firmware version shown on screen is 50221.

2

With weak esp32 internal pullup voltage rises too slowly.
Try with 1k or 2.2kΩ external pull-up to 3.3V.
And enable uart debug on esphome to capture data what you actually receive.

3

I imagine that the intern pull-up resistance activated with INPUT_PULLUP mode is not enough ?

4

That’s what I wrote…

5

thanks a lot.
it was effectively that.
I used a 4.7kΩ and it work perfectly.

6

You are welcome!
Be aware, it has to be pulled up to 3.3V, not 5V.