In mid eighties I was doing crazy stuff, like programming the Z80 CPU board (that I constructed using a spaghetti of wires and jumpers
on cascaded breadboards. I wrote the code in Hex, directly using the CPUs instruction set.. the most difficult task was when I wanted
to jump to a subroutine.. then I needed to calculate the target address using pure binary additions and counting the bytes between the
two addresses, after putting current registers' values in the stack.. Todays programmers read this and see it as Chinese language.
I was so fascinated by the instruction "DJNZ" which means Decrement and Jump if Not equal to Zero.. used it loops.. in high-level languages
it's called For Next Loop. Another funny instruction was the "SEX" instruction in the Motorola 6809 which meant Sign EXtend, but was replaced
in subsequent CPUs, may be an ISIS manager became CEO of Motorola..
That was the time of real programming when we talked directly to the microprocessor.. we are now just wheel drivers who can't change a tire.
Thanks to our bus drivers like Erel.