I need to be able to expand my inputs on a PIC it has 3 analogue inputs, ideally an IC which has around 8 inputs to one output in the form of 1-wire, serial, I2C or just an analogue signal. The PICs I can use are Genie 18 or Genie E28. I have tried using a resistor network with switches in circuit wizard which wouldn't work as when any of the switches were pressed the voltage would just act as a digital input at the full 6v instead of different values for each switch. (https://i0.wp.com/www.g7smy.co.uk/gallery/var/resizes/blog/resistor_ladder2.png)