Hi everyone, I wanted to make some tries on PIC programming and needed some circuits. When I was searching I found some circuits but they seem confusing to me. http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/29/devre.jpg In the circuit picture attached I wonder why are there the 4.7kΩ ressistances on the left hand side? I think they only form parallel loops and don't provide anything apart from more energy consumptation. What do I miss? I also cannot understand the lines in the microcontroller. Can someone show the simplified streams?