EDL1 - Emu Black V3

Hello everyone,
I have a question about the EDL-1 Data Logger.
The data logger isn’t working properly, or rather, it’s not being recognized by the EMU Black V3 (FW 3.055). The green LED is constantly lit, and the blue LED is flashing slowly. I performed the firmware update to version 1.21 on the EDL-1.
At least, I assume it worked. The right LED flashed red for a few seconds and then the LED turned solid green again. And the Firmware.bin file in the root of the SD card was automatically renamed to Firmware.bak. It looks like the update worked.
I installed the EDL-1 according to the instructions from August 2025.
TXD Emu-Black to RXD EDL-1 and rotated. 12 volt power supply, ground to chassis ground, and the shielding also to chassis ground.
The “Set Datalogger Time” function worked, strangely enough.
At least there were no error messages.
Are there any known dependencies with the EDL-1 ?
Thank you for your support.

Have you updated edl firmware?

Yes on V1.21. As described above.