Slimmelezer: Invalid string length

Received my Slimmelezer today, and immediately hooked it up to the DSMR meter.
Integration is working in HA. I receive IP address, uptime, MAC, … information from the Slimmelezer.
Unfortunately no readings from the meter itself. All the entities regarding to metering data have the state ‘unknown’.
When I open the ESP home web interface of the Slimmelezer I receive the following output in the error log below:

Invalid string lengthe
[E][dsmr:138]: 0-0:96.1.4(50215)
Invalid string lengthe
[E][dsmr:138]: 0-0:96.1.4(50215)
Invalid string lengthe
[E][dsmr:138]: 0-0:96.1.4(50215)

Anyone else having the same issue? Any clues ?

I was able to resolve this issue with the help from comments on Github:

Turns out this is a known issue with Belgian Sagemcom meters.
Here are the steps that I took to resolve the issue:

  1. If not installed: Install ESPHome add-on in Home Assistant;
  2. Create a new entry for the slimmelezer device in ESPHome.
    name this profile ‘slimmelezer’ (without the quotes).
    For the WIFI information: use a random SSID and password, since this will be replaced in step 4 from the config.
  3. A sample configuration is created for you, replace this configuration entirely with the one found on Marcel Zuidwijk’s website: SlimmeLezer configuration – Marcel Zuidwijk
    Replace the wifi information, with your correct SSID and password.
    - ssid: "my-wifi-network"
      password: "mySecretPassword"
  1. Add a configuration line to the configuration you just copy pasted, as described by Piet Petrus, found here:
    These extra lines prevent the error from happening.
  2. Click the Install button in the ESPHome editor, and choose manual download. You can choose to flash it directly to your Slimmelezer, if the device is connected via USB to your computer, and you’re using Google Chrome or Microsoft Edge.
    Unfortunatly, this didn’t work well for me so I chose to download the .bin file and flash it with the following tool:
  3. When flashing is complete, reconnect the Slimmelezer to the P1 port again and be patient.
    It took up to 5 min for me before the device showed up again in HomeAssistant.

I hope this helps you resolving the issue I had with the Slimmelezer.

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