The document discusses the control unit in computer architecture. It notes there are two kinds of control units: hardwired and microprogrammed. A hardwired control unit is made up of sequential and combinational circuits to generate control signals. It has the advantage of fast operation but the disadvantage that the wiring must be changed if the design needs to be altered. The document includes a block diagram of a hardwired timing and control unit.

1. COMPUTER ARCHITECTURE
NAME-RAHUL SHARMA
COURSE-BCA 3RD SEM (E)
FACULTY-MRS. SUMAN SINGH

2. BLOCK DIAGRAM OF HARDWIRED
CONTROL UNIT
CONTROL UNIT

3. KINDS OF CONTROL UNIT
• THERE ARE TWO KINDS OF CONTROL UNIT
1) HARDWIRED CONTROL UNIT
2) MICRO PROGRAMMED CONTROL UNIT

4. HARDWIRES CONTROL UNIT
• CONTROL UNIT IS MADE UP OF
SEQUENTIAL AND COMBINATIONAL
CIRUITS TO GENERATE THE CONTROL
SIGNALS.
• ADVANTAGE-CAN BE OPTIMEZED TO
PRODUCED FAST MODE OF
OPERATION
• DISADVANTAGE-REQUIRE CHANGE IN
WIRING IF THE DESIGNED HAS TO BE
CONTROLLED

5. Computer Architecture BCA203 by Suman
Singh
5
Hardwired Timing And Control Unit
Control unit of Basic Computer
Instruction register (IR)
15 14 13 12 11 - 0
3 x 8
decoder
7 6 5 4 3 2 1 0
I
D 0
15 14 . . . . 2 1 0
4 x 16
decoder
4-bit
sequence
counter
(SC)
Increment (INR)
Clear (CLR)
Clock
Other inputs
Control
signals
D
T
T
7
15
0
Combinational
Control
logic