Hi, I am working on a project. Using PIC18F2525. I always thought that when the MCLR/VPP pin is activated or 0V, the program counter is reset to the beginning of the code, and all the pins output a logic 0 or 0V. In my case, when the MCLR is on, pins C3, C4, C5 are high or 5V. When MCLR is off or at 5V, these pins behave exactly as they should according to my code. This would be no big deal, but for my project I need to hit reset or activate MCLR every once in a while, and I do not want pins C4 and C5 to be high at the same time. This happens when I hit reset and MCLR is activated. Now whats the deal with pullup resistors? Does every input and output pin need to have a pullup resistor? I usually don't use them. Could this be the problem? Thanks guys.