I wasn't able to find any material related to this topic, so I'm going to post it here.
In this thread I'm going to provide some basic facts that prove that it is possible to emulate any computer architecture in Excel (or any Excel-compatible software). I'm going to provide some fundamental digital logic that can be easily implemented in Excel.
I'm planning to extend this thread over time.
Basic stuff (combinational logic)
Firstly, you'll need to enable iterative calculations. This allows you to create flip-flops or any other circuits that have any feedback.
Different connections will be stored in different cells. Cells can take two values (for now, at least): 1 and 0.
So let's create the NOT function.
NOT(0) = 1
NOT(1) = 0
There are two ways to implement it:
1. = 1 * NOT(cell)
NOT(cell) will return TRUE or FALSE (the values will change depending on your language), so we have to convert the result to integers.
It is unreasonable to perform complex operations on numbers using discrete logic gates, so you can use the standard addition, subtraction, lookup etc. functions. However, you might want to convert multibit integers into discrete signals and vice versa.
For splitting, the easiest solution is to convert the number into binary and then split the binary number as a string.
For combining the signals, you can concatenate all the bits and then convert the final string to a decimal number.