Looking for the right document(s)

Other Hardware 3rd Party Boards
1

I just got BLINK to work on my new Arduino Nano board. The provided sketch contains the command:

pinMode (13, OUTPUT);

My chart for the ATMEGA328 associates physical pin 17 with PB5 and D13. Where is the document that tells me to call it '13' as opposed to PORTB5 or D13 or 17??

The ATMEGA328datasheet.pdf in the chart on Page 11 refers to pages 86 and 87 of some document. What document and where do I get it?

Is there a fairly complete programming manual for whatever this C-like language is called? If so, where?

Ken :~

2

The pin mapping that the Arduino team used to abstract the port/pin names to pin numbers is unique to the arduino project and will not show up in any Atmel document or datasheet or general C/C++ manual. Here is a spreadsheet someone put together to help, call it the arduino rosetta stone. :wink:

https://spreadsheets.google.com/pub?key=rtHw_R6eVL140KS9_G8GPkA&gid=0

I use the arduino reference section as a starting point for usage info and move on from if needed.

Lefty

3

It is a bit confusing but when you pass pin numbers to pinMode, digitalRead, digitalWrite, or analogWrite, the value is the Arduino digital pin number. You find them printed on the Arduino board. The analogRead function uses the Arduino analog input pin numbers (0-5 for most, 0-7 for the Nano). The analog input pins can also be used as digital pins: analog inputs 0..7 are also known as digital pins 14..21.

If you want to use direct port access you can find look-up tables that show the mapping from port and bit to Arduino pin. You can also look at the schematic for your board.

4

I took out my magnifying glass and found D13 printed on the Nano board.

I also found the HELP section of the Arduino-0022 'Digital Pins'. Hopefully everything will make sense.

Thank you all :slight_smile:

5

I took out my magnifying glass and found D13 printed on the Nano board.

It's more obvious (and sensible) on the full-sized Arduino boards, where the digital pins are simply numbered right to left across the top from 0 to 13... More legible too.
The nano is just a re-packaging with the same chip pin mapping as the full-sized version, rather than having the pins renumbered to make sense on the (new) package.