Abstract: A single chip dual processor is implemented combining a microcontroller and digital signal processor. An unitary instruction set is utilized for programming both processors in one source program which is stored in a single external program memory. While compiling the source program, a compiler distinguishes which instructions are to be executed by which processor and designates each instruction to be stored in the appropriate memory space allocated to the processor which is to execute the instruction.

Abstract: An unsigned integer multiply/divide circuit is implemented with an unconventional non-restoring division algorithm which always subtracts the divisor from the partial dividend regardless of whether the divisor is greater than the partial dividend or not, a hybrid carry lookahead and carry select adder construction where both portions run in parallel, and control lookahead features which avoid interim calculation wait delays. The division algorithm is further modified in order that the same hardware configuration primarily consisting of storage registers, an adder, a multiplexer, and a shifter can be used for both multiplication and division operations.