Arduino Pro Mini

Introduction

The Arduino Pro Mini is a microcontroller board based on the ATmega328.It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, an on-board resonator, a reset button, and holes for mounting pin headers. A six pin header can be connected to an FTDI cable or Spark fun breakout board to provide USB power and communication to the board.There are two version of the Pro Mini.One runs at 3.3V and 8 MHz, the other at 5V and 16 MHz.

Arduino Pro Mini

The Pro Mini is not physically compatible with Arduino shields (you could still hard-wire the Mini up to any Arduino shield).The Pro Mini uses the same ATmega328 and also has same 14 digital i/o pins,6 analog pins as in Uno.

Though it differs from Uno by some hardware changes such as,Size-Pro mini is just 1.3x0.70" and it is about 1/6th the size of the Arduino Uno,Operating voltage-Pro mini has only one regulator on board either 3.3V or 5V unlike Uno which has both 5V and 3.3V and the Clock Speed is 8MHz fro 3.3v model which is half the speed of Uno.

As said before,there are two versions of Pro mini(3.3v and 5v).So how to know the difference between this two will be worth mentioning.There is a voltage regulator on the Pro mini(red box shown in the image) which makes the difference.i.e If the label of that regulator is given as KB33 mean it is 3.3v model and KB50 means 5v model.Also you can measure the voltage between the Vcc and Gnd pin which determines the model.

Technical Specifications

1. Microcontroller - ATmega328
2. Operating Voltage - 3.3V or 5V (depending on model)
3. Input Voltage - 3.35 -12 V (3.3V model) or 5 - 12 V (5V model)
4. Digital I/O Pins - 14 (of which 6 provide PWM output)
5. Analog Input Pins - 6
6. DC Current per I/O Pin - 40 mA
7. Flash Memory - 32 kB (of which 0.5 kB used by bootloader)
8. SRAM - 2 kB
9. EEPROM - 1 kB
10. Clock Speed - 8 MHz (3.3V model) or 16 MHz (5V model)

Arduino Pro Mini Pinouts

• RAW: For supplying a raw (regulated) voltage to the board
• VCC: The regulated 3.3 or 5 volt supply
• GND: Ground pins
• RX: Used to receive TTL serial data
• TX: Used to transmit TTL serial data
• Digital I/O pins(2 and 3): These pins can also be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value
• Digital I/O pins(3, 5, 6, 9, 10, and 11): They can also be configured to provide 8-bit PWM output
• Digital I/O pins(10, 11, 12 and 13): They can also be configured as SPI pins-10 - (SS), 11 - (MOSI), 12 - (MISO) and 13 - (SCK)
• Analog input pins: A0 to A7 in which A4 and A5 can also be used as IIC pins where A4 - (SDA) and A5 – (SCL).
• Reset: The microcontroller can be reset by bringing this pin low

FTDI Platinum board

How to Program Arduino Pro Mini

Hardware and Software Required

• Arduino Pro Mini 3.3v
• Arduino IDE(1.0.6V)

For programming the Pro mini,either we need a FTDI TTL-232R-3V3 USB - TTL Level Serial Converter Cable or SparkFun FTDI Basic Breakout Board and USB Mini-B cable which connects the Pro mini to the computer.Here FTDI Platinum board is used as shown in the image.While connecting the FTDI board to Pro mini,the Gnd of Arduino should face Gnd of FTDI.

Program to turn on the Led

Like other Arduino,the Pro mini also has on board Led which we are going to blink it with one second delay.Before that,select the correct board and port in Arduino IDE.Here we are using Pro mini 3.3v/ATmega 328 board.

void setup() 
{
   pinMode(13, OUTPUT);// initialize digital pin 13 as an output.
}
 void loop()// the loop function runs over and over again forever 
{
 digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)
 delay(1000);              // wait for a second
 digitalWrite(13, LOW);    // turn the LED off by making the voltage LOW
 delay(1000);              // wait for a second
}