Hi, I'm new to this board and Arduino/AVR stuff so please forgive me if I'm in the wrong place or don't use the correct terminology.
I am in the process of repurposing a guitar foot switch which has an embedded Atmega8a microcontroller. I've figured out the ICSP connections, installed a bootloader and am now testing it. It has a bank of 6 switches which connect ground to pins 9-14 (PD and PB). Before I test the switches I want to make sure there's no chance of causing damage so here's my question - why are there are 1k external pullup resistors on those lines? I thought that those pins had internal pullup resistors so the external ones seem redundant. I assume I can test the switches without setting the pins to use the internal resistors but I'm so new to this that I need to know what's going on with the external resistors before I proceed. Thanks for taking the time.