4. INTRODUCTION TO REGISTER
• FLIP FLOP IS 1 BIT MEMORY CELL
• TO INCREASE THE STORAGE CAPACITY , WE HAVE TO USE A GROUP OF FLIP
FLOP
• THIS FLIP FLOP IS KNOWN OF REGISTER.
• THE N BIT REGISTER CONSIST OF “N” NUMBER OF FLIP FLOP AND CAPABLE OF
STORING “N BIT” WORD.
• ONE FLIP FLOP IS USED TO STORE 1 BIT OF DATA WHILE THE GROUP OF FLIP
FLOP WILL USE TO STORE MORE THAT 1 BIT DATA. FOR EXAMPLE IF WE WANT
TO DESIGN 4 BIT REGISTER , SO WE HAVE TO USED 4 FLIP FLOPS.
5. EXAMPLE : DESIGN 4 BIT REGISTER
- ONLY FOR STORING THE DATA NOT TOGGLING
D3 D2 D1 D0
Q Q Q Q
CLK
Clock is internally
connected and applied at
same time.
Clock connected to all four
flip flops.
Clock is not generated
individually for every
operation but generated at
same time .
6. DATA FORMAT AND REGISTER
CLASSIFICATION
•DATA CAN BE ENTERER IN SERIAL OR PARALLEL FORM
•SERIAL – 1 BIT AT A TIME
•PARALLEL -- ALL BITS AT A TIME ( MULTIPLE BITS)
FF3
FF2 FF1 FF0
7. FF3 FF2 FF1 FF0
Register
Serial
D
1011
D
1 0 1 1
Serial method
Output Q
9. CLASSIFICATION OF REGISTER
• CLASSIFICATION OF REGISTER IS DEPENDING ON:
a) INPUT /OUTPUT
i. SISO ( SERIAL INPUT SERIAL OUTPUT)
ii. SIPO (SERIAL INPUT PARALLEL OUTPUT)
iii. PISO ( PARALLEL INPUT SERIAL INPUT)
iv. PIPO (PARALLEL INPUT PARALLEL OUTPUT)
b) APPLICATION
i. SHIFT REGISTER
ii. STORAGE REGISTER
10. SISO ( serial input serial output)
FF3 FF2 FF1 FF0
Register
Input
D
1011
Output Q
Serial output
Serial input
14. SHIFT REGISTER
APPLICATION 1:
IF YOU WANT DATA TO BE SHIFTED FROM FF3 FF2 FF1
FF0, THEN PRODUCE OUTPUT Q.
FF3 FF2 FF1 FF0
Register
Input
D
1011
Output Q
Serial output
Serial input
15. SISO
With each clock pulse, data are shifted to the right one
position, and the rightmost bit is transferred out.
16. STORAGE REGISTER
• APPLICATION 2:
• IF YOU WANT YOUR DATA JUST TO BE STORE AND THEN USE IT WHEN YOU
NEED IT AND NO SHIFTING OF THAT DATA.
