Arduino Mega2560 R3 pinouts photo

Inspired by Nick’s UNO pinout I did a similar one for the Arduino Mega2560 R3.

Annotations are color coded. Green have the same function and position as the Arduino UNO R3. Red are differences, where the functionality has moved on Mega2560 compared to UNO. In general, this means that the UNO put several functions on one pin and these have moved to separate pins on the Mega. Blue is for differences due to added functionality (extra pins).

I find it convenient to use the GND pins near to the analog input pins as analog grounds, and to use the GND on the end block for digital grounds, when linking to external circuitry.

Update: correct SCL to SCK, correct colors, call out second ICSP header

Very nice! Thank you!

Good job. Only thing I can see is a nomenclature on the '2560 ICSP header the SCL should be SCK like the other SPI pins.

spcomputing: Good job. Only thing I can see is a nomenclature on the '2560 ICSP header the SCL should be SCK like the other SPI pins.

Thanks! And yes, it should. I corrected it. Also, since the header has the same position and pinout as the UNO, it should be green.

While I was at it, I clarified that the DC input is center positive, and called out the second ICSP socket as well.

My friend, we have a nice tool here. Thanks for breaking out the 16u2 ICSP!

Not that it is needed, but one more thing jumped out. The I2C "extensional" pins and pins 20 and 21 could be tied "visually", but it could be a little too busy.

Good job again, I like the polarity declaration as well.

Wow that’s great job! Thanks for sharing! I wish I found this picture yesterday when I was trying to figure out why my clock and wave shield didn’t work when I moved it from Unto to 2560 :slight_smile: It safe me hours! :slight_smile: I’m going to print it out and keep at my desk.
That’s interesting that there are 2 more I2C connections (unlabeled on the board) above AREF, I thought they weren’t connected anywhere. I wonder if one above IOREF does something too?

bratan: I wonder if one above IOREF does something too?

i know this is a bit late but looking at the schematics (bottom left, power)http://arduino.cc/en/uploads/Main/arduino-mega2560_R3-schematic.pdf it isnt connected to anything at all

I wonder if one above IOREF does something too?

It's a no connection at this time. The arduino folks just added and reserved the pin position for their future use.

Lefty

Thanks for sharing your work!

Newbie alert: So which are d0-d7 lines as you would use for say LiquidCrystal()?

Thanks, K..

kallen: Newbie alert: So which are d0-d7 lines as you would use for say LiquidCrystal()?

Thanks, K..

They are the same as a UNO unless you have a real SPI interface on the LCD. The current Arduino IDE is default to 4-bit, but if you want to use 8-bit, you will have to specify it in the initialization parameters (LiquidCrystal lcd(rs, rw, enable, d0, d1, d2, d3, d4, d5, d6, d7)).

Check the out the LiquidCrystal tutorial for more detail: http://arduino.cc/en/Reference/LiquidCrystalConstructor

Also, for a lot of LCD Shields, the 4-bit initialization is different than the tutorial/examples (i.e. LiquidCrystal lcd(8, 9, 4, 5, 6, 7);)

I got confused by the photo of the Arduino Mega 2560 board with labeled pins. I think that the two pins at the top of the double header over pins 22 and 23 on the right side of the board are 5V pins. Are pins 23, 25, 27, and 29 digital pins? The labels on the photo confused me into thinking that pins 23, 25, 27, and 29 are 5V pins.

Ah, I hadn't thought of it like that but I can see how it could be read that way. I will move the "5V pins" label and make it clearer.

Nice Job, thank’s for sharing!

My (reference to company selling counterfeit product removed by moderator) Mega2560 board doesn’t have the connectors for I2C like your picture shows.
Any idea, where to connect them?
THX

Guess I found them: digital Pins 20 and 21 are SDA and SCL…

I have the (reference to company selling counterfeit product removed by moderator) board too I found it's best to print the schematic to see which pins and ports that where extened to the stackable connector. Im using 6 external interrrupts on mine Don

Do i see it right, that there are 15 PWM outputs (2-13 + 44 45 46)? several sites of the shop do say, that there are just 14. The 15 would be important for my project.

Nantonos, Nice Work on this!

May I use this on the http://ArduinoInfo.Info WIKI? I’d link back to your original as well.

Thanks!

A table of pins 1-100 on the Atmega2560 with the corresponding Arduino Mega pin number mappings would be ideal.

Hi there,

I noticed that the pdf drawing on the Arduino Product web page shows 2 crystals 16Mcs, however there's only one on the board?? Furthermore, the downloadable eagle files do not open in my Eagle: Invalid data error

I am experiencing communication probs, possibly coming from one clock source for the 2560 & 16U2, derived from 1 crystal, only.

Could you please clarify?

Thank's

hk

Hi there, http://pighixxx.com/megapdf.pdf http://pighixxx.com/atmega2560v3_0.pdf

Greeting and fun Andreas