I am doing my project using Arduino UNO and Arduino Ethernet board W5100, now I pile it up together.
After reading some sources, they said that SPI communication using 4 lines, here:http://dev.emcelettronica.com/i2c-or-spi-serial-communication-which-one-to-go
It means when I connect my arduino UNO to my computer, it uses SPI to communicate.
It also means that when I connect my arduino UNO to my Ethernet Board using 4 pins, it uses also SPI to communicate, doesn't it? Correct me if I am wrong.
Then, what the example of I2C communication?
What about the LAN jack on the Ethernet Board, what type of communication it uses? SPI or I2C?
I am newbie in this electronic device, and kindly hope your help.