The SIM800L module needs special attention because it operates at 3.3V logic levels while Arduino uses 5V. We need a voltage divider circuit to protect the SIM800L from damage. If you are new to the ...

This project monitors voltage using a potentiometer connected to an Arduino. When the voltage reaches 4.8V or higher, the system automatically sends an SMS and makes a phone call using the SIM800L GSM ...

Fig. 2 shows the circuit diagram of the automatic daily meal reminder system. It is built around the Arduino Uno (MOD1), RTC3231 (MOD2), SIM800L GSM module (MOD3), 16×2 LCD I2C module (MOD4), a buzzer ...

A Wearable Alert System for Underground Mining Workers based on Arduino with GSM ... The proposed system consists of temperature sensor, heartbeat sensor, gas sensor, display unit and GSM module. The ...

arduino gsm security alarm. ... // RX and TX pins to communicate with GSM module #define msg_key 7 #define call_key 8 #define end_key 9 String number ="0000000000"; // Add the 10-Digit Mobile Number ...

The degradation of river ecosystems poses a significant threat to biodiversity and human health due to industrial and agricultural pollutants. This paper presents the design and development of a ...