46+ Arduino Leonardo Spi Pinout Pics. Usb jack, power jack and reset button are quite in line with each other and are surfaced on one side of the board. Typically there are three lines common to all the devices:

In System Programming
In System Programming from microtherion.github.io
Read about 'arduino leonardo pinout, atmega 32u4 pin mapping, schematics, eagle files, and more!' on element14.com. For arduino leonardo, the pins on the icsp header are not connected to any of the digital i/o pins as they are. Spi pins 10 (ss), 11 (mosi), 12 (miso) and 13 (sck):

For long distance communication we use the i2c.

These pins are used for spi communication. The spi lines have some differences among different arduino boards, especially the new leonardo. Following figure shows the pinout of arduino leonardo. Since spi communication also has its disadvantages such as 4 essential pins and limited within a device.