* The TXS instruction does not affect any flag, while all other transfer instructions do.
* The BIT instruction copies bit 6 of the memory location to VF, regardless of any arithmetic overflow concept.
* The CLV (Clear Overflow Flag) instruction exist , but not the SEV (Set Overflow Flag) instruction.
* On NMOS, INC A and DEC A instructions do not exist. They do exist on CMOS.
* The NOP instruction takes 2 full-cycles. This is the minimum amount of cycles an instruction can take. It is necessary because, while the instruction itself does nothing, it still has to increment the 16-bit PC register.