The bit-sliced microprocessors with the high-speed of bipolar technology have become available building blocks for implementing a general purpose CPU of mini-level computer system with a 16-bit data path and macro-instruction cycle time of a few micre-seconds.
For the above reason, the Intel Series 3000 Bipolar Microcomputer Set was chosen for emulation of the PACE, National Semiconductor Corp.'s 16 bit microprocessor which has fairly powerful instruction set and architecture but is rather slow due to the speed limitation of the PMOS technology.
The microprogram written by Mr. Ill-Soo Ahn for thes purpose was improved in reducing the cycle time of macro-instruction, saving the control memory, and adding other functions for an actual implementation of CPU.
As a result, compared with the previous program, in average 2 to 4 micro-cycles per a macro instruction were reduced, and one fourth of the control memory space was saved.
Interrupt service and bootstrapping routines, and custom instruction DIV, which was tailored to divide 16 bit number in 40 micro-seconds using the nonrestoring algorithm, were implemented.
