Pin	GPIO	Anmerkung						Verwendung
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D3	GPIO0	IO, 10k Pull-up					Button links (+)
D4	GPIO2	IO, 10k Pull-up, BUILTIN_LED	Button mitte (-)
D5	GPIO14	IO, SCK							Button rechts (Mode)
D7	GPIO13	IO, MOSI						DHT22 Temp/Hum Sensor
D0	GPIO16	IO								Heizungsansteuerung
D2	GPIO4	IO, SDA							I2C SDA
D1	GPIO5	IO, SCL							I2C SCL
D6	GPIO12	IO, MISO						vorgesehen für PIR-Sensor

D8	GPIO15	10k Pull-down, SS				-- nicht verwendet --


Hardware via I2C:
 - Display 1602			Addr: 0x27
 - Lux-Sensor BH1750	Addr: 0x23