This is an arduino project for controlling the temperature and humidity of air and ground and controlling the windows in the greenhouse. The measurement statistics and data about the operation of the system are stored on the SD memory card. The current state is output to the terminal via the UART.
As a base board, the Arduino board is the STM32F103C8.
Power is provided from a 12-volt uninterruptible power supply via a DC/DC converter that outputs 5V/2A.
Real-time clock DS 3231 is used to synchronize processes and save the time of statistics. EEPROM 24C32 on the RTC board is needed to save the settings.
The SD card is needed to record the log files.
The HP203B sensor module is used to measure air temperature and atmospheric pressure. It is connected to the I2C bus and is powered by 3.3 volts from the Arduino board.
The AM2320 is used to measure temperature and relative humidity. It is connected to the I2C bus and is powered by 5 volts.
Sensors DS18B20 in hermetic design are used to control air and soil temperature. It is connected to a single-wire bus and is powered from 5 volts.
To control the external load, relay modules are used. The relays are controlled via the shift registers 74НС595 connected cascaded and connected via the SPI bus.
The 74HC165 shift registers with parallel-in and serial-out, connected to the SPI bus to expand the input ports. The inputs use protection on a reverse diode which provides an active low level.
