The UNO up close and personnel

So let’s is started showing you the details of the Arduino UNO, I'll point out the inputs and outputs and a few key components of interest.

I will show you the genuine boards and also a few of my clones I have floating around. You will be able to see the differences between the Duel in Line Package (DIP) and the Surface Mounted (SMD) Atmel Atmega328 chips.



*Let’s get started*

I better make you aware of the system I'm going to use.  In the photos below you will find red and orange lines around parts of the board that have a corresponding number next to them, these numbers will correspond to a list below with the explanation of the part / interesting information!

You will also notice as we make progress on the different variations some points will be covered in the above photo, to save repeating myself I'll just say "As above".

*Lets really get started!*

First up the DIP genuine board

Arduino UNO - DIP

1. Reset button, quickly starts the program off again. A bit like a restarting your computer.
2. Inbuilt LED, it is tied to the digital pin 13 and will light up even if you are using it for another purpose!
3. Ground pin / 0 voltage
4. Digital pins from pin 1 all the way to pin 13
5. Orange - These pins are duel use, firstly they are normally digital pins but they also are used for serial communication.
6. Orange - PWM or Pulse Width Modulation pins, simply means you can get an analogue type output from a digital pin (another posting coming in the future on this)
7. Power on LED, Simple :)
8. ICSP or In Circuit Serial Programming, used to upload the boot loader to the micro controller and also can be used to program the micro controller too. Normally not too much use unless you have the need to buy the micro controllers separately to use in separate projects and program them easily with the Arduino board
9. Micro controller, it’s the Atmel Atmega328p. This thing is the heart, soul and brain of the Arduino
10. Analog pins, A0 to A5. This can take analogue inputs an example of this could be a potentiometer
11. Power pins, from left to right 3.3+ volts, 5+ volts, two ground (0 volts/negative)
12. External power jack, gives you the ability to run the Arduino without using the USB cable with a suitable wall plug adaptor
13. 16Mhz resonator for the USB to Serial chip used for the timing of communications
14. Resettable fuse, adds to the protection that most USB on computers already have, you can never be too careful
15. USB to Serial chip, it’s a Atmel Atmega8u2
16. USB socket

Next up is the genuine surface mounted variant;

Arduino UNO - SMD

1. Inbuilt LED, it is tied to Digital pin (as above)
2. Ground pin / 0 voltage
3. Digital pins (as above)
4. Power on LED
5. ICSP (as above)
6. Reset button
7. The "brain" this time it is the same Atmel Atmega328 but in a SMD format
8. Analogue pins (as above)
9. Power pins (as above)
10. Resonator for the Atmel Atmega328
11. External power jack
12. 16Mhz resonator for number 14
13. Resettable fuse (as above)
14. USB to Serial chip, it’s a Atmel Atmega8u2
15. USB socket 
16. TX and RX LED, they flash when being used

1. Orange - These pins are duel use, firstly they are normally digital pins but they also are used for serial communication.
2.  Orange - PWM or Pulse Width Modulation pins, simply means you can get an analogue type output from a digital pin (another posting coming in the future on this)

 Moving on to the DIP clone

This is a "Funduino" clone of the UNO, it’s the only one that's DIP. Seems to be a bit more expensive than the SMD versions I purchased in the past, can't say I notice any different quality or performance.

1. Reset button (as above)
2. USB to Serial chip, it’s a Atmel Atmega8u2
3. Inbuilt LED, it is tied to Digital pin (as above)
4. Ground pin / 0 voltage
5. Digital pins 1 to 13 (as above)
6. Power on LED
7. ICSP (as above)
8. Micro controller it’s the Atmel Atmega328p. This thing is the heart, soul and brain of the Arduino
9. Analogue pins (as above)
10. Two ground pins / 0 voltage
11. +5 volt pin
12. +3.3 volt pin
13. Reset pin 
14. External power jack
15. 16Mhz resonator for 2
16. Resettable fuse
17. USB jack

And finally the SMD clone

1. Reset button
2. Power on LED
3. Ground pin / 0 voltage
4. Digital pins (as above)
5. RX and TX LED's
6. Analogue pins (as above)
7. Ground pins / 0 voltage
8. +5 voltage pin
9. +3.3 voltage pin
10. Reset pin 
11. Another +5 voltage pin
12. Inbuilt LED, it is tied to Digital pin (as above)
13. External power jack
14. CH340G USB to Serial chip (needs a driver that have to be downloaded, it’s not found inbuilt in Windows, Mac and Linux like the others)
15. 12Mhz resonator for 14
16. USB socket