The roles assigned to the different registers are, in most cases, only conventions. A register that is somewhat special is the next instruction word (NIW) register. NIW always denotes the 16-bit integer that follows the current instruction word. If the NIW register appears anywhere within the instruction, the program counter is incremented by two words rather than by only one. This mechanism makes it possible to allow an immediate value to replace any operand in an instruction. From the perspective of the processor’s dataflow, NIW is just another register.