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Field level

Wetter station

For the weather station I decided for the P03/3-Modbus from Elsner.

wetterstation

With it I can get the weather data: Brightness (east, south and west sun), wind speed, temperature and precipitation.

With the Modbus variant I want to keep the possibility open to connect several participants (in special room sensors) to the control system via the bus system.

The heating system

My heating consists of the 20qm solar collectors and the "romantic" stove in the living room as well as an ETA SH20 twin.

eta_thump

During the installation I saw that a maintenance interface is attached to the display.

On inquiry with the manufacturer I got the RS232 protocol and thus the possibility by a CM1241 to access it.

Here the protocoll:

  1. Byte startsign: alwas ’{’ == hex 0x7B
  2. Byte Servicekennung
  3. Byte Servicekennung
  4. Byte Anzahl der Nutzdatenbytes
  5. Byte Prüfsumme: alle Nutzdatenbytes addiert, modulo 256
  6. ab 6. Byte Nutzdaten

last Byte stoppsign alwas ’}’ == hex 0x7D

settings of serial interface:

19200 Baud, 1 Startbit, 8 Datenbits, 1 Stoppbit, NoParity, NoHandshake

Herewith I inform the heating control that it should send out the actual values cyclically:

#SEND_PTP_start(REQ := #cmd.eta_start,
                "PORT" := #CP_Adress,
                BUFFER := #frame_start);
#cmd.eta_start := FALSE;

#SEND_PTP_cmd(REQ:=#cmd.eta_cmd,
              "PORT":=#CP_Adress,
              BUFFER:=#frame_cmd);