Can't get SDM72D-M v2 to work

[floppybl]

Hello everyone,

My heat pump is currently connected to an SDM72D-v2 from Eastron via a D1 Mini with a converter (link). The D1 Mini is integrated into Home Assistant via ESPHome (directly through the HA add-on) and works fine.

Now, however, I want to integrate the meter as a heat pump meter in some tools that doesn't support ESPHome. Therefore, I am now trying to switch the entire setup to Tasmota since I can create the integration that way.

What have I done?
I flashed a D1 Mini with a self-created Tasmota firmware according to the Smart Meter guide (link) with all the things regarding to D1 Mini. Then I added the script (link) in Tasmota. So far, so good.

When I now connect the D1 to the converter, the converter just starts blinking wildly. No data is coming through, of course. Since I am using pins D1 and D2, I have adjusted line 4 in the script accordingly:

+1,5,mN1,0,9600,SDM72D,4,1

However, this doesn’t change anything. No other settings have been made on the D1 Mini. The measurement table is displayed, but no data is received. I tried also 3V3 and 5V, still the same behaviour.

What am I doing wrong?