Program Control Register

Holds address of the next instruction to be executed. Maintains step-by-step counting sequence and causes the computer to read successive instructions already stored in the memory. If a branch instruction is encountered, th address part of the branch instruction becomes the address of the next instruction in the PC registered. When the contents of PC register is transferred to the MAR, a read cycle is initiated. The instruction placed in the MBR is then transferred to the instructionregister.