4-Bits Shift Register (BCD), D flip-flops

A shift register stores and shifts data.
Used in memory, communication, and data conversion.
A 4-bit shift register handles 4-bit data.
This project designs a 4-bit shift register.
D flip-flops hold and shift binary data.
Clock pulses control the data movement.
Simulate and implement shift register design.
3. Theory
A shift register is a sequential logic circuit that consists of a chain of flip-flops, typically D flip-flops, connected in a serial manner. The key operations of a shift register are:
Shifting: Data is moved from one flip-flop to another, either left or right, depending on the configuration.
Loading: The register can be loaded with data in parallel or serial mode.
Output: The data can be retrieved either serially or in parallel.
There are four primary types of shift registers:
1. Serial-In Serial-Out (SISO): Data is input and output serially.
2. Serial-In Parallel-Out (SIPO): Data is input serially but output in parallel.
3. Parallel-In Serial-Out (PISO): Data is input in parallel but output serially.
4. Parallel-In Parallel-Out (PIPO): Data is input and output in parallel.
Each flip-flop stores one bit, and the data shifts one position for every clock pulse.
Block Diagram:
Design Description:
The 4-bit shift register is composed of four D flip-flops connected in series.
The clock signal is shared among all flip-flops.
The input data is serially fed to the first flip-flop (Q0), and on each clock pulse, the data shifts to the next flip-flop (Q1, Q2, Q3).
Depending on the mode, the register can accept data serially or in parallel, and output can be obtained either serially or in parallel.