Logical and Shift Micro-operations Computer Organization and Architecture by Ravinder Nath Rajotiya - March 22, 2021May 14, 20210 Logical Shift micro-operations: The logical operations that are performed on the contents of the processor register are called as the logical micro-operations. These micro-operations are AND, OR, INVERT, XOR etc. are performed on individual bits of the registers As an example, logical exclusive-OR micro-operations can be written as: X: R3 <-- R1 ⊕ R2 This RTL syntax describes that R3 is update with the result of the exclusive-OR operation on the contents of R1 and R2 when the control signal X goes high. We are aware that a ‘+’ means an arithmetic addition as well as a logical OR operation. To avoid the confusion in the use of the symbols the OR operation will be indicated by ‘V’ and the arithmetic operation by ‘+’ symbol.
Instruction Set 8086 8086 Microprocessor by Ravinder Nath Rajotiya - October 14, 2020April 28, 20210 Platforms for writing 8086 assembly programs. Assembly level language program for the 8086 processors can be written in the following platforms. Directly as hex codes fed into the RAM and executed on a trainer kit DOS debug utility of windows Writing the text file in notepad or gedit and then assembling using the MASM, TASM, NASM assemblers etc. We can also write and run the program in the IDE of C or C++ Classification of instructions 8086 instructions may be classified as: Classification based on size of the instruction: As discussed in topic on instruction format 8086 instruction can be from 1 to 6 byte long. The first two bytes indicate the OPCODE and the addressing Classification based on the addressing modes: The