So you don't load the pin. This is a dual use pin, you can use it for the LED or anything else. The SPI library uses it for the SCLK. The op amp makes sure you can put the full digital load on the pin.
So you don't load the pin. This is a dual use pin, you can use it for the LED or anything else. The SPI library uses it for the SCLK. The op amp makes sure you can put the full digital load on the pin.