Truth Table Waveforms Serial IN Parallel OUT The last flip flop, i.e., FF-0, is set, and the word is stored when the clock's negative edge arrives. Similarly, the last bit of the binary number, i.e., 1, is passed to the data input D 0, and the clock is applied. The third flip flop, i.e., FF-1, is set, and the word is stored when the negative edge of the clock hits again. The next bit of the binary number, i.e., 1, is passed to the data input D 1, and the clock is applied. The second flip flop, i.e., FF-2, is set, and the word is stored when the next negative edge of the clock hits. The next bit of the binary number, i.e., 1, is passed to the data input D 2. The first flip flop, i.e., FF-3, is set, and the word is stored in the register at the first falling edge of the clock. We will apply the clock, and this time the value of D 3 is 1. The LSB bit of the number is passed to the data input D in, i.e., D 3. When the clock signal application is disabled, the outputs Y 3 Y 2 Y 1 Y 0 = 0000. The block diagram of the 'Serial IN Serial OUT' is given below. This process remains the same for the remaining flip flops. The output Y 3 is passed to the data input d 2 of the next flip flop.

The D3 input of the third flip flop, i.e., FF-3, is directly connected to the serial data input D3. If we pass the binary number 1111, the LSB bit of the number is applied first to the Din bit. Initially, all the flip-flops are set in 'reset' condition i.e. In SISO, a single bit is shifted at a time in either right or left direction under clock control. In 'Serial Input Serial Output', the data is shifted 'IN' or 'OUT' serially. The shift register is classified into the following types: A Shift Register, which shifts the bit to the left, is known as 'Shift left register', and it shifts the bit to the right, known as 'Right left register'.

The flip flops are connected in such a way that the first flip flop's output becomes the input of the other flip flop.Ī Shift Register can shift the bits either to the left or to the right. So, the number of bits of the binary number is directly proportional to the number of flip flops. To form an n-bit shift register, we have to connect n number of flip flops. The bits stored in registers shifted when the clock pulse is applied within and inside or outside the registers. A group of flip flops which is used to store multiple bits of data and the data is moved from one flip flop to another is known as Shift Register.