Test #3 Flashcards
Which of the following statements are TRUE about a microoperation? Select all that apply.
A fundamental operation on data stored in registers
Data transfer from one register to another is one category of microoperations
Subtraction may be a microoperation
Performed in one clock pulse
We considered three categories of microoperations
A fundamental operation on data stored in registers
Data transfer from one register to another is one category of microoperations
Subtraction may be a microoperation
Performed in one clock pulse
The notation:
R1 <- R2, R2 <- R1
indicates that Registers 1 and 2 swap their contents in one clock pulse
True
We can connect 8 registers, each register of which has 16 bits, to a common data bus as follows. Select all statements that are TRUE
May use multiplexers
Use size 16 x 1 MUXes
Need 8 MUXes
May use tri-state buffer gates
Would need 8 tri-state buffer gates for each data bus line
May use multiplexers
May use tri-state buffer gates
Would need 8 tri-state buffer gates for each data bus line
The output from a data bus created using MUXes can be loaded into multiple registers during one clock pulse
True
The following statement may be implemented as a microoperation:
A <- A + B
True
What special property of the Exclusive-OR gate did we discuss that allows us to build an adder-subtractor circuit as shown in Figure 4-7 (see below)?
If one input is one, the exclusive OR gate inverts the other input
The logical unit we studied in Figure 4-10 (see below) performs four different logical operations.
True
What do you get if your perform a logical left shift on the following bits?
11001010
10010101
00110010
10010100
01100101
00101000
10010100
If we perform a circular left shift on: 00101110 , the result is 01011100
True
If we perform an arithmetic right shift on: 10001101, the result is: 11000110
False
An arithmetic left-shift divides the binary number by 2
False
An arithmetic right-shift never produces overflow.
True
In the following microoperation:
p + q : R1 R2 + R3, R4 R5 R6
The āvā symbol stands for the logical OR operation
True
Suppose the circuit of Figure 4-7 has the following input values.
M = 0
A = 0110
B = 0011
then the outputs are as follows:
S = 1001
C4 = 0
True
Suppose the circuit of Figure 4-7 has the following input values.
M = 1
A = 0110
B = 0011
then the outputs are as follows:
S = 0011
C4 = 1
True
Given Figure 4-9, determine what operation is performed on inputs A and B given the following values:
s1 = 0
s0 = 1
cin = 1
Subtraction
Increment A
Decrement A
Addition
Transfer A
Subtraction
Given Figure 4-9, determine what operation is performed on inputs A and B given the following values:
s1 = 1
s0 = 0
cin = 1
Subtraction
Increment A
Decrement A
Addition
Transfer A
Increment A
Given Figure 4-9, determine what operation is performed on inputs A and B given the following values:
s1 = 1
s0 = 1
cin = 1
Subtraction
Increment A
Decrement A
Addition
Transfer A
Transfer A
In Lab 6, we added two 2-bit numbers together using the 7483 4-bit adder chip. You could receive extra credit by adding two 4-bit numbers together.
True
In Lab 7, we implemented the microoperation:
A <- A + B
using the following chips:
Two 7495 4-bit register chips
One 7483 adder chip
One 74157 MUX chip
True
5 / 5 pts
We used four 2x1 multiplexers in Lab #7
True
Given Figure 4-10 and the inputs below, what operation is sent out on the Ei output line?
S = 1
S = 1
Logical AND of two bits
Logical OR of two bits
Exclusive OR of two bits
Negation of B bit
None of these
None of these
Given Figure 4-13 and the inputs below, what operation is sent out on F output line:
S = 0
S = 0
S = 1
S = 0
C = 1
Addition
Subtraction
Increment A
Decrement A
Transfer A
Increment A
For the circuit in Figure 4-13 to perform a logical operation, the control lines must equal 11
False
