ASCII ART, to copy into sketches or online.
ASCII ART by busyducks
UNO
+-----+
+----[PWR]-------------------| USB |--+
| +-----+ |
| GND/RST2 [ ][ ] |
| MOSI2/SCK2 [ ][ ] A5/SCL[ ] | C5
| 5V/MISO2 [ ][ ] A4/SDA[ ] | C4
| AREF[ ] |
| GND[ ] |
| [ ]N/C SCK/13[ ] | B5
| [ ]IOREF MISO/12[ ] | .
| [ ]RST MOSI/11[ ]~| .
| [ ]3V3 +---+ 10[ ]~| .
| [ ]5v -| A |- 9[ ]~| .
| [ ]GND -| R |- 8[ ] | B0
| [ ]GND -| D |- |
| [ ]Vin -| U |- 7[ ] | D7
| -| I |- 6[ ]~| .
| [ ]A0 -| N |- 5[ ]~| .
| [ ]A1 -| O |- 4[ ] | .
| [ ]A2 +---+ INT1/3[ ]~| .
| [ ]A3 INT0/2[ ] | .
| [ ]A4/SDA RST SCK MISO TX>1[ ] | .
| [ ]A5/SCL [ ] [ ] [ ] RX<0[ ] | D0
| [ ] [ ] [ ] |
| UNO_R3 GND MOSI 5V ____________/
\_______________________/
http://busyducks.com/ascii-art-arduinos
ATMEGA 2650
+-----+
+----[PWR]-------------------| USB |--+
| +-----+ |
| GND/RST2 [ ] [ ] |
| MOSI2/SCK2 [ ] [ ] SCL[ ] | D0
| 5V/MISO2 [ ] [ ] SDA[ ] | D1
| AREF[ ] |
| GND[ ] |
| [ ]N/C 13[ ]~| B7
| [ ]IOREF 12[ ]~| B6
| [ ]RST 11[ ]~| B5
| [ ]3V3 +----------+ 10[ ]~| B4
| [ ]5v | ARDUINO | 9[ ]~| H6
| [ ]GND | MEGA | 8[ ]~| H5
| [ ]GND +----------+ |
| [ ]Vin 7[ ]~| H4
| 6[ ]~| H3
| [ ]A0 5[ ]~| E3
| [ ]A1 4[ ]~| G5
| [ ]A2 INT5/3[ ]~| E5
| [ ]A3 INT4/2[ ]~| E4
| [ ]A4 TX>1[ ]~| E1
| [ ]A5 RX<0[ ]~| E0
| [ ]A6 |
| [ ]A7 TX3/14[ ] | J1
| RX3/15[ ] | J0
| [ ]A8 TX2/16[ ] | H1
| [ ]A9 RX2/17[ ] | H0
| [ ]A10 TX1/INT3/18[ ] | D3
| [ ]A11 RX1/INT2/19[ ] | D2
| [ ]A12 I2C-SDA/INT1/20[ ] | D1
| [ ]A13 I2C-SCL/INT0/21[ ] | D0
| [ ]A14 |
| [ ]A15 | Ports:
| RST SCK MISO | 22=A0 23=A1
| ICSP [ ] [ ] [ ] | 24=A2 25=A3
| [ ] [ ] [ ] | 26=A4 27=A5
| GND MOSI 5V | 28=A6 29=A7
| G | 30=C7 31=C6
| N 5 5 4 4 4 4 4 3 3 3 3 3 2 2 2 2 5 | 32=C5 33=C4
| D 2 0 8 6 4 2 0 8 6 4 2 0 8 6 4 2 V | 34=C3 35=C2
| ~ ~ | 36=C1 37=C0
| @ # # # # # # # # # # # # # # # # @ | 38=D7 39=G2
| @ # # # # # # # # # # # # # # # # @ | 40=G1 41=G0
| ~ | 42=L7 43=L6
| G 5 5 4 4 4 4 4 3 3 3 3 3 2 2 2 2 5 | 44=L5 45=L4
| N 3 1 9 7 5 3 1 9 7 5 3 1 9 7 5 3 V | 46=L3 47=L2
| D | 48=L1 49=L0 SPI:
| | 50=B3 51=B2 50=MISO 51=MOSI
| 2560 ____________/ 52=B1 53=B0 52=SCK 53=SS
\_______________________/
http://busyducks.com/ascii-art-arduinos
NANO
+-----+
+------------| USB |------------+
| +-----+ |
B5 | [ ]D13/SCK MISO/D12[ ] | B4
| [ ]3.3V MOSI/D11[ ]~| B3
| [ ]V.ref ___ SS/D10[ ]~| B2
C0 | [ ]A0 / N \ D9[ ]~| B1
C1 | [ ]A1 / A \ D8[ ] | B0
C2 | [ ]A2 \ N / D7[ ] | D7
C3 | [ ]A3 \_0_/ D6[ ]~| D6
C4 | [ ]A4/SDA D5[ ]~| D5
C5 | [ ]A5/SCL D4[ ] | D4
| [ ]A6 INT1/D3[ ]~| D3
| [ ]A7 INT0/D2[ ] | D2
| [ ]5V GND[ ] |
C6 | [ ]RST RST[ ] | C6
| [ ]GND 5V MOSI GND TX1[ ] | D0
| [ ]Vin [ ] [ ] [ ] RX1[ ] | D1
| [ ] [ ] [ ] |
| MISO SCK RST |
| NANO-V3 |
+-------------------------------+
http://busyducks.com/ascii-art-arduinos
PRO MINI
D0 D1 RST
GND GND VCC RX TX /DTR
+--------------------------------+
| [ ] [ ] [ ] [ ] [ ] [ ] |
| FTDI |
D1 | [ ]1/TX RAW[ ] |
D0 | [ ]0/RX GND[ ] |
| [ ]RST SCL/A5[ ] RST[ ] | C6
| [ ]GND SDA/A4[ ] VCC[ ] |
D2 | [ ]2/INT0 ___ A3[ ] | C3
D3 |~[ ]3/INT1 / \ A2[ ] | C2
D4 | [ ]4 /PRO \ A1[ ] | C1
D5 |~[ ]5 \ MINI/ A0[ ] | C0
D6 |~[ ]6 \___/ SCK/13[ ] | B5
D7 | [ ]7 A7[ ] MISO/12[ ] | B4
B0 | [ ]8 A6[ ] MOSI/11[ ]~| B3
B1 |~[ ]9 SS/10[ ]~| B2
| [RST-BTN] |
+--------------------------------+
http://busyducks.com/ascii-art-arduinos