Shift registers
A shift register is a group of flip flops that are used to store multiple bits of data, and the data is moved from one flip flop to another.
To form an n-bit shift register, we need to connect the n number of flip flops, therefore the number of bits of the binary number is directly proportional to the number of flip flops.
Shift registers are classified into the following types:
- Serial In Serial Out
- Serial In Parallel Out
- Parallel In Serial Out
- Parallel In Parallel Out
- Bi-directional Shift register
- Universal Shift register
Serial In Serial Out
In “serial in serial out” or SISO, the data is shifted in and out serially.
Serial In Parallel Out
In “serial in parallel out”, the data is shifted serially to the flip flops, and the outputs are fetched in parallel.
Parallel In Serial Out
In “parallel in serial out”, the data is entered in a parallel way in the flip flops, and the output is fetched serially.
Parallel In Parallel Out
In “parallel in parallel out”, the data is shifted parallelly to the flip flops, and the output is fetched in parallel too.
Bi-directional Shift register
Bi-directional shift registers are used to perform multiplication and division operation as it requires the register to move in the left or right direction.
Universal shift register
Universal shift registers are such registers that can load the data in a parallel way and shift it in both directions.
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