Arduino UNO (rev. 1) & Screw Terminal Adapter
There is nothing to say about Arduino that hasn't already been said!
This project makes use of a genuine Arduino UNO board (the Atmega328 microcontroller was deemed adequate for the task), but any 5V/16MHz Arduino can be used as well.
| Pin | I/O | Description |
|---|---|---|
| A0 | IN | from coin container microswitch |
| A1 | IN | from amount reset pushbutton |
| A2 | IN | from door microswitch |
| A3 | - | (not used) |
| A4 | OUT | data line (SDA) for I2C communication with LCD display |
| A5 | OUT | clock line (SCL) for I2C communication with LCD display |
Note: the project doesn't make use of any analog feature. A0, A1 and A2 are used
as digital input pins and are configured to use internal pullups).
| Pin | I/O | Description |
|---|---|---|
| 0 | IN | USART RX from coin acceptor |
| 1 | - | (not used) |
| 2 | - | (not used) |
| 3 | OUT | PWM to passive buzzer |
| 4 | OUT | to coin acceptor (reject coins signal & 3mm red LED) |
| 5 | OUT | to solenoid lock driver |
| 6 | - | (not used) |
| 7 | OUT | to ultrasonic sensor (TRIG) |
| 8 | IN | from ultrasonic sensor (ECHO) |
| 9 | OUT | to RFID reader - reset pin |
| 10 | OUT | to RFID reader - (SPI Slave Select) |
| 11 | OUT | to RFID reader - (SPI MOSI) |
| 12 | IN | from RFID reader - (SPI MISO) |
| 13 | OUT | to RFID reader - (SPI clock) |
To make connections dependable, a screw terminal was used.
(next - Coin Acceptor)