2 8-bit Multiplication

Doing an 8-bit multiply using the hardware multiplier is simple, as the examples in this chapter will clearly show. Just load the operands into two registers (or only one for square multiply) and execute one of the multiply instructions. The result will be placed in register pair R0:R1. However, note that only the MUL instruction does not have register usage restrictions. Figure 2-1 shows the valid (operand) register usage for each of the multiply instructions.