Microprocessor notes

The Simple-As-Possible (SAP)-1 computer is a  very basic model of a microprocessor explained  by Albert Paul Malvino . The SAP-1 design  contains the basic necessities for a functional  Microprocessor. Its primary purpose is to develop  a basic understanding of how a microprocessor  works, interacts with memory and other parts of  the system like input and output. The instruction  set is very limited and is simple. SAP (Simple-As-Possible)-1 is the first stage in the evolution toward modern computers. • SAP is Simple-As-Possible Computer. The type of  computer is specially designed for the academic  purpose and nothing has to do with the  commercial use. The architecture is 8 bits and  comprises of 16 X 8 memory i.e. 16 memory  location with 8 bits in each location, therefore , need 4 address lines which either comes from  the PC (Program Counter which may be called  instruction pointer) during computer run phase or  may come from the 4 a

•  An instruction is a binary pattern designed inside a microprocessor to perform a specific function . •  8085 has 246 instructions. •  Each instruction is represented by an 8-bit binary value. Classification  of instruction set There are 5 Types, (1) Data Transfer Instruction, (2) Arithmetic Instructions, (3) Logical Instructions, (4) Branching Instructions, (5) Control Instructions,