MICROPROCESSOR AND MICROCONTROLLER

Detailed explanation-1: -In execution of any instruction first cycle is op-code fetch cycle. After that depending upon the given instruction the memory read/write and I/O read/ write cycle occurs.

Detailed explanation-2: -Four steps of the machine cycle Fetch-Retrieve an instruction from memory. Decode-Translate the retrieved instruction into computer commands. Execute-Execute the computer commands. Store-Send and write the results back in memory.

Detailed explanation-3: -The 8085 instruction cycle consists of one to six machines cycles or operations. 2) Machine cycle: It is the time required for completing a single operation. This operation can be accessing memory for read/write operation or accessing I/O device. There can be 3 to 6 clock periods or T-states in a machine cycle.

Detailed explanation-4: -Each clock cycle is called as T-states. An instruction’s execution length is usually measured in a number of T-states. The first step of executing any instruction is the Opcode fetch cycle. Operation steps: (4 T-States.)