I'm new with coding and programming microcontrollers. And I'm currently working on a combination lock program that requires only two push buttons and 4 LEDs as indicators. I found a site that provides the program, but uses a PIC16F84 microcontroller. In my case, I have to use a PIC16F84A. To my knowledge the only difference between the two PICs are the delay. However, when I tried changing the delay, the build was unsuccessful. I hope someone can help me with this. This was the program that I found on the internet that uses the PIC16F84 > http://www.piclist.com/techref/piclist/cheapic/combo.htm. But I only made slight changes to it, like the processor and what not. But I wasn't sure whether to change the ports. But in my project I'm only using Port B as my input/output. Can someone please point out on where to change the programs so it could be compatible to PIC16F84A? In my project I use a 4MHz crystal oscillator, not following the project from the website that I just shared.