Arduino – LCD 1602A I2C – PASSWORD PROTECTED DOOR ACCESS With Relay – KY-019
Hello world! Today i made a simple code to control a electric strike lock with a Password/ Access Code using a 1 channel relay. I don’t have such a lock but i demonstrated it with a lamp attached to the relay. Check the next step for the schematic code & Parts list.
(I know! I wrote access wrong in the video..don’t mind the typo..lol.)
Step 1: Schematic, Code & Parts List
You need these following librarys
Wire it up like the schematic and it should work after uploading,
if your not seeing anything, try change your I2C Address i will include a Code to scan your address.
You can change this at the line shown below which you can find on line 14 of the code.
- #define I2C_ADDR 0x27
Most common I2C addresses.
- PCF8574 = 0x20,
- PCF8574A = 0x38,
- PCF8574AT = 0x3F
- PCF8574T = 0x27
- Arduino uno, I used the RobotDyn Uno.
- 1 Channel Relay KY-019
- Keypad 4×4
- LCD 1602 with I2C
- Electrical Strike Lock (Not needed to test the code, you will see if relay go’s on or off.)