Hi
This time I came up with an hybrid programming project ( traditional Arduino code programming and visuino programming).HMI display are always hectic to program.There are many Display options for adding graphical user interface to Arduino boards. Most of them however require considerable amount of memory, and processing time, and are not suitable for Arduino boards with limited memory, and processing power such as Arduino UNO or Arduino Nano. When the memory is limited, and an advanced user interface is needed, the Smart Programmable Serial Nextion Displays are a popular choice. The Itead offers a free Graphical Nextion Editor for designing the user interface of the display..however process of developing graphical interface for user is simplified by nextion editor.
In this project we will be doing seperate programming for Arduino mega controller for nextion display and Arduino Uno fingerprint scanner/sensor R305 and enable serial communication between both the Arduinos.
For nextion display we will use Arduino mega by programming it in visuino and for fingerprint sensor we will use Arduino Uno programmed using traditional method using adaafruit fingerprint library.
We will make an LED on/off using the biometric fingerprint sensor R305.If user fingerprint matches with the fingerprint enrolled with the sensor and it's corresponding user guidance messages will be displayed on the nextion display.
I am very grateful to biaon mitov for developing the advanced visuino software for programming which simplifies the process remarkably.
Hardware needed:
Softwares needed( All latest versions)
please note:
Arduino uno has used software serial as fingerprint serial data port and used hardware serial port to communicate with Arduino mega.
Arduino mega uses its serial1 hardware port for fingerprint data and serial2 for communicating with Arduino uno.
connections between fingerprint sensor and arduino uno.
Connection between arduino mega(serial2) and nextion
connection between uno and mega(serial1)
please watch video tutorial for this part.
Note this step must be done prior to connecting with the arduino uno.
For fingerprint enrollment in sensor i will recommed to connect fingerprint sensor to usb to ttl converter and then connect it to usb port of computer.
Interfacing with Arduino
It is quite easy to use the fingerprint reader with Arduino by using this library from Github. It uses software serial pins to communicate with the reader. The connections should be as follows
connection between usb to TTL and fingerprint sensor :
than open the windows software for enrollment :
Upload this code to arduino uno after finger enrollment process is over.
then connect fingerprint sensor to arduino uno.
After uploading code open serial terminal in arduino ide to see the instructions for the user.
if they appear it means upto here you are going correct otherwise find the error.
Please check my previous instructables if any problem with the display programming part.
you have to simply add txt "t0" component on page0 , futher i have added one more txt component but you can omit.
Note: you must generate font for txt component
txt"t0" component will display fingerprint message and "t1" is for static text.
Make sure same txt have same attributes (check image).
To program the Nextion Display, you will need to Download and Install the Nextion Editor.
Start the Nextion EditorFrom the Menu select |File|New| .
We need to add a text component, and configure it to have 200 characters length.
To program the Nextion Display with the Nextion Editor you need to connect it with a USB to TTL Serial Converter to your computer or transfer tft file to sdcard.
Communication between both arduinos is achieved by connecting arduino uno's Tx pin to serial1 Rx of arduino mega.
you can watch schematics.