Broken Connection with HMS-2000-4T EU-Version

[sgraf83-hessen]

What happened?

No / poor Connection between openDTU and Hoymiles HMS-2000-4T

Transmission statistics:
1% => OK
90% => fault
9% => incomplete

Debug console
thousands of "Interrupt received"
some "Frame defected / corrupted"
message

To Reproduce Bug

_ install the newest release v25.2.3
_ playing around with several DTU settings (dBm, frequencies - incl. 1h waiting periods)
_ shutdown all existing hoymiles and dtu devices in my household
_ distance between both devices ~50cm
_ sufficient power supply

Expected Behavior

see valid data from my inverter

Install Method

Pre-Compiled binary from GitHub releases

What git-hash/version of OpenDTU?

v25.2.3

What firmware variant (PIO Environment) are you using?

opendtu-generic_esp32.bin

Relevant log/trace output

Interrupt received
17:46:40.543 > Interrupt received
17:46:40.562 > Interrupt received
17:46:40.580 > Interrupt received
17:46:40.587 > RX Period End
17:46:40.587 > Middle missing
17:46:40.587 > Request retransmit: 1
17:46:40.587 > TX RequestFrame 865.00 MHz --> 15 A0 0B 88 54 80 18 49 72 81 40 
17:46:40.612 > Interrupt received
17:46:40.631 > Interrupt received
17:46:40.643 > Interrupt received
17:46:40.673 > Frame kaputt
17:46:40.703 > Interrupt received
17:46:40.721 > Frame kaputt
17:46:40.741 > Interrupt received
17:46:40.761 > Interrupt received
17:46:40.781 > Interrupt received
17:46:40.801 > Interrupt received
17:46:40.841 > Interrupt received
17:46:40.861 > Interrupt received
17:46:40.880 > Interrupt received
17:46:40.886 > RX Period End
17:46:40.886 > Middle missing
17:46:40.886 > Retransmit timeout
17:46:40.895 > TX AlarmData 865.00 MHz --> 15 A0 0B 88 54 80 18 49 72 80 11 00 67 A3 95 EE 00 00 00 00 00 00 00 00 D4 51 6A 
17:46:40.921 > Interrupt received
17:46:40.942 > Interrupt received

Anything else?

No response

Please confirm the following

• I believe this issue is a bug that affects all users of OpenDTU, not something specific to my installation.
• I have already searched for relevant existing issues and discussions before opening this report.
• I have updated the title field above with a concise description.
• I have double checked that my inverter does not contain a W in the model name (like HMS-xxxW) as they are not supported.

[tbnobody]

Sounds to me like bad cabling or misconfigured pin_mapping.json..
It is definetly not a general firmware issue as it works for my HMS inverter without any problems..
converting this to a discussion in Q/A section

So please doublecheck your wiring.... Another possibility would be, that there is a lot traffic at your selected frequency. Try to change the DTU frequency a little bit (just 1 or two ticks)

[MichaMEG]

Is a suitable antenna installed?
A different one is required than for WiFi!
I use these:
https://www.amazon.de/gp/aw/d/B0978Q7N7C?psc=1&ref=ppx_pop_mob_b_asin_title
Both devices too close together can also be a problem.

[sgraf83-hessen]

@MichaMEG I hope so, I bought this DTU as ready-to-go product online at diamex.de

[MichaMEG]

I probably also had an unsuitable antenna installed.