Microcontroller with sensor board

This is my first design, shield kit for Arduino MEGA2560 board. The shield kit provides BME280 sensor interface, 20x4 LCD display, 4x4 matrix keypad, DS1307 RTC, RS232 port and buzzer. We can use it for displaying barometric pressure, humidity, temperature. Keypad is available for parameter settings. An optional buzzer can be used for alarm.

BME280-MEGA2560 kit

The shield kit features:






Barometric (BME280)



Humidity (BME280)



Temperature (BME280)



DS1307 Real time clock



20x4 LCD display module

6-bit DIO

RS232 port

9600 UART

Hardware UART TX1,RX1


small buzzer

DIO pin 7


4x4 matrix keypad

8-bit DIO

The controller platform is MEGA2560 board with CH340 USB chip.

Figure 2: MEGA2560 board with CH340

Hardware descriptions: BME280 sensor module is interfaced to the MEGA2560 chip using I2C port J3, SDA and SCL pins. LCD display connector, JR1 is 4-bit interfacing with digital pins, D4, D5, D6, D7 (5,4,3,2) and RS (12), E(11). R4 is for contrast adjustment. R2 is current limit for black light. Keypad is 4x4 matrix membrane switch. It uses PORTC, 8-bit. U1 is RS232 converter. The hardware UART U1, converts TXD1, RXD1 TTL to RS232 level at VB1. RTC chip, DS1307 is also interfaced using I2C. BT1 is for +3V Lithium coin battery. J11 is optional I2C device.


Figure 4: Complete assembled shield kit. 


Figure 5: BME280-MEGA2560 shield put on the MEGA2560

Keypad is membrane 4x4 matrix key. The 8-pin socket of the keypad connects the shield at J8. Refer to schematic, it uses PORTC, PC0 to PC7.

Figure 6: With 4x4 membrane keypad


Figure 7: BME280 module and optional I2C header.

More details for kit or pre-assembled please contact wichit.sirichote@gmail.com

Download Sample BME280 object file displays barometric pressure, humidity, temperature, date/time on the LCD.
BME280 interfacing



17 February 2018