1. Registers
P.Shrinijha
II M.Sc CS

2. INTRODUCTION
 A register is a group of flip-flops suitable for storing binary
information.
 Each flip-flop is a binary cell capable of storing one bit of
information .
 An n bit register has a group of n flip-flops and is capable of
storing binary information containing n bit.
 The register is mainly used for storing and shifting binary data
entered into it from an external source.

3. 4 Bit Shift Register
 A number of registers are
available in MSI circuits.
 The register has an common
clock-pulse input
 There are four input I1,I2,I3 and
I4 in 4 bit shift register.
 There are four output Q1,Q2,Q3
and Q4 in 4 bit shift register.
 This register uses the D flip-flop
 A group of flip-flops sensitive to
pulse duration is called a latch

4. Shift Registers
• A register cabable of shifting binary
information either to left or right is called
shift register
• Shift Register
 Serial Shifting
 Parallel Shifting

5. ShiftRegister Types
• Serial-in Serial-out(SISO)
• Serial-in Parallel-out(SIPO)
• Parallel-in Serial-out(PISO)
• Parallel-in Parallel-out(PIPO)

6. Serial-in Serial-out Shift Register
• Serial-in to Serial-out (SISO) - the data is shifted serially “IN”and “OUT” of
the register, one bit at a time in either a left or right direction under clock
control.

7. Shift Right Register
• Data may be shifted right(from high to lower bits)

8. Shift Right Register

9. Shift Left Register
• Data may be shifted left(from lower to higher bits)