Sorry if this might be a duplicate, but I'm not sure how to google this.

I know that from computer science that the registers are for high-speed variables so I've been trying to minimize my use of ram. How much of a difference can this actually make? What is the speed differences of something like this:

Code:


I have seen references to people talking about counting T-states of their programs but how do I know how long each line takes?

Again sorry if this has been asked a million times before.

Yes, in general using registers will be faster than using memory. However, memory does include the bytes of the instructions themselves. So for example, loading a constant into a register will be slower than loading a register into it. This is what leads to optimizations like XOR A instead of LD A,0.

In any case, you can use helpful references like this to see the technical information for every instruction: https://clrhome.org/table/