A control unit which support 128K control word memory. Processor hardware support 64 control signal and 8 flags . What is the size of horizontal control word in byte.

(A) 10 byte
(B) 10.5 byte

(C) 11 byte

(D) 3 byte


Answer: (C)

Explanation: Computer supported control word format:

Branch condition = 0
Flag = 8
Control signal = 64
Control memory = 128k

Control word memory is 128 k i.e. 17 bits
64 control signal and it is given that horizontal control word is supported.
So, 64 bit will be there for control signals.
3 bit for 8 flag.
Total 3 + 64 + 17 is 84 bits
Byte = 84 bits / 8 = 11 byte.
So, option (C) is correct.


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