I'm coming from a similar background and asked myself that exact question :) These two books helped me much already: Programming from the Ground Up by Jonatha

I'm coming from a similar background and asked myself that exact question :) These two books helped me much already: Programming from the Ground Up by Jonathan Bartlett - A very good introduction to assembly Learning Computer Architecture with Raspberry Pi by Eben Upton - Great read about the inner working of memory and the CPU, with reference to the past and how things developed