I am building a board with ISP capability with SPI pins. I have a MAX306 16 channel MUX/DEMUX on the SCK,MISO and MOSI pins. I have a RESET switch which pulls the RESET pin to GND.
Can I connect the three SPI pins to the MUX and still use them for programming? Do I need pull ups on those lines? Also what about the RESET pin? Since I have a switch on it, do I have to manually keep it pressed when I am programming my AVR with the three SPI pins?
Also do I have to add anything to my code/ set any fuses to enable ISP programming? I am planning to use the AVRISP for future in system programming if needed.