1. Counters and registers Eng.Maha Alqubali

2. Registers Registers are groups of flip-flops, where each flip- flop is capable of storing one bit of information. An n-bit register is a group of n flip-flops. The basic function of a register is to hold information in a digital system and make it available to the logic elements for the computing process Eng.Maha Alqubali

3. Registers Four bit Register: D C Q D C Q D C Q D C Q D0 D1 D2 D3 Q0 Q1 Q2 Q3 clk D0 D1 D2 D3 Q0 Q1 Q2 Q3 clk Symbol Circuit Eng.Maha Alqubali

4. Types of Registers 1) Shift Registers. 2) Cyclic Registers. 3) Parallel In-Serial Out. Eng.Maha Alqubali

5. Counters A counter is a sequential circuit that counts. Types of counters: 1- Asynchronous counter: For these counters an external clock signal is applied to one flip flop and then the output of preceding flip flop is connected to the clock of next flip flop. 2- Synchronous counter : In synchronous counter all the flipflop receive the external clock pulse simultaneously. Eng.Maha Alqubali