Description: Pops TOS and stores it x positions deep, overwriting the
pre-existing stack entry. Indexing begins at 0 and is counted
after popping the TOS. Thus, STSP+0 deletes the NOS, equivalent
Description: Pops TOS and stores it x positions deep, overwriting the
pre-existing stack entry. Indexing begins at 0 and is counted
after popping the TOS. Thus, STSP+0 deletes the NOS, equivalent