Editing Z3 (computer) (section)

== Instruction set ==
The Z3 operated as a [[stack machine]] with a stack of two registers, R1 and R2.  The first load operation in a program would load the contents of a memory location into R1; the next load operation would load the contents of a memory location into R2.  Arithmetic instructions would operate on the contents of R1 and R2, leaving the result in R1, and clearing R2; the next load operation would load into R2.  A store operation would store the contents of R1 into a memory location, and clear R1; the next load operation would load the contents of a memory location into R1.<ref name="Rojas_1997_Legacy"/>{{rp|page=8}}

A read keyboard operation would read a number from the keyboard into R1 and clear R2.  A display instruction would display the contents of R1 and clear R2; the next load instruction would load into R2.<ref name="Rojas_1997_Legacy"/>{{rp|page=8}}