$$\eqalign{ & \,\,\,\,\,\,\,\,\,\,\,\,\,MBR\,\,\,\,\,\,\, \leftarrow PC \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,MAR\,\,\,\,\,\,\, \leftarrow X \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,PC\,\,\,\,\,\,\,\,\,\,\,\, \leftarrow Y \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,Memory\, \leftarrow MBR \cr} $$
Which one of the following is a possible operation performed by this sequence?
The, $$ALU$$, the bus and all the registers in the data path are of identical size. All operations including incrementation of the $$PC$$ and the $$GPRs$$ are to be carried out in the $$ALU.$$ Two clock cycle are needed for memory read operation-the first one for loading address in the $$MAR$$ and the next one for loading data from the memory but into the $$MDR.$$
The instruction $$''add$$ $$R0$$, $$R1''$$ has the register transfer interpretation $$R0 < = R0 + R1.$$ The minimum number of cycles needed for execution cycle of this instruction is
The, $$ALU$$, the bus and all the registers in the data path are of identical size. All operations including incrementation of the $$PC$$ and the $$GPRs$$ are to be carried out in the $$ALU.$$ Two clock cycle are needed for memory read operation-the first one for loading address in the $$MAR$$ and the next one for loading data from the memory but into the $$MDR.$$
The instruction $$''call$$ $$Rn,sub''$$ is a two word instruction. Assuming that $$PC$$ is incremented during the fetch cycle of the first word of the instruction, its register transfer interpretation is
$$$\eqalign{
& Rn < = PC + 1; \cr
& PC < = M\left[ {PC} \right]; \cr} $$$
The minimum number of $$CPU$$ clock cycles needed during the execution cycle of this instruction is :