S0 meters have a switching output for the S0 pulses (e.g. 1000 pulses per kWh). The cFos Charging Manager can evaluate these pulses at an RS232 interface and make them available in the form of a "COM port" counter. In this way, a counter can be connected to a Raspberry or PC with little effort. A USB RSR adapter and suitable terminals are required:
RS232 USB Adapter
Klemmen für RS232
The S0 output of the counter must switch the RX pin to ground from the RS232 interface. Please note that most S0 counters use transistor outputs and the current can only flow in one direction. Therefore, please rotate the wire pair if necessary. You can then set up a "COM Port" counter in the cFos Charging Manager. Enter the COM port provided by the USB adapter as the address. Then you have to set the pulses per kWh that your meter supplies.
Note: The RS232 interface officially has a 12V level, but in practice it is much less. But it should be enough for a few metres of cable (maybe 3-5m).
With the above configuration, the "COM Port" meter also provides digital inputs, e.g. to evaluate control signals from outside, such as the relay contact of a ripple control receiver or an inverter of a solar system. You can connect the signals CTS, DSR, RI and CD to earth at the RS232 interface. These can then be evaluated as input1 to input4 (sequence: CTS, DRS, RI, CD) in the meter by means of formulas. If your meter has the device ID M5 in the cFos Charging Manager, for example, you can access M5.input1, M5.input2, M5.input3 and M5.input4 using formulas.