Register Transfer Micro-operations

These micro-operations as the name proposes transfer information from one register to another. The information doesn't change during these micro-operations. A register transfer micro-operation can be designed as: R1← R2. The ←symbol implies that contents of register R2 are transferred to register R1. R2 here is a source register whereas R1 is a destination register. We will employ this notation throughout this section. Please note that the following important points about register transfer micro-operations.

• For a register transfer micro-operation there should be a path for data transfer from output of source register to input of destination register.
• Additionally the destination register must have a parallel load capability as we expect the register transfer to take place in a predetermined control condition.
• A common path for connecting different registers is via a common internal data bus of the processor. In general size of this data bus must be equal to number of bits in a general register.