Landis & Gyr E320 not with IEC 62056-21 component but with SML component

[Karosm]

@mabe

At first I tried with the same hardware setup, i.e. GPIO5 as RX. But I received only a garbeled mess. As aquaticus recommends using the HW UART, I switched to the HW RX, i.e. GPIO3.

For that baud rate I would go with GPIO5.
Hardware serial on D1 mini might/might not work, depends on the usb serial circuit of the specific board. In any case, you need to set logger baud_rate to 0 if you want to use pins 1 / 3 for uart component.