teach-ict.com logo

THE education site for computer science and ICT

2. The Registers used

A number of registers inside the CPU are involved with the cycle. These are shown below

registers in fetch cycle

The registers are:-

  • The MDR (Memory Data Register)
  • The MAR (Memory Address Register)
  • Program Counter
  • Accumulator
  • Instruction Register

We will next explain how these registers are used in each stage of the cycle.

Challenge see if you can find out one extra fact on this topic that we haven't already told you Click on this link: Fetch Decode Cycle