8255 Operation Modes MCQs : This section focuses on the "8255 Operation Modes". These Multiple Choice Questions (MCQs) should be practiced to improve the 8255 Operation Modes skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
If the value of the pin STB (Strobe Input) falls to low level, then
A. input port is loaded into input latches
B. input port is loaded into output latches
C. output port is loaded into input latches
D. output port is loaded into output latches
Question 2
In BSR mode, only port C can be used to
A. set individual ports
B. reset individual ports
C. set and reset individual ports
D. programmable I/O ports
Question 3
In the I/O mode, the 8255 ports work as
A. reset pins
B. set pins
C. programmable I/O ports
D. only output ports
Question 4
The feature of mode 0 is
A. any port can be used as input or output
B. output ports are latched
C. maximum of 4 ports are available
D. all of the mentioned
Question 5
The feature of mode 2 of 8255 is
A. single 8-bit port is available
B. both inputs and outputs are latched
C. port C is used for generating handshake signals
D. all of the mentioned
Question 6
The level of the signal ERROR(active low) becomes ‘low’ when the printer is in
A. Paper end state
B. Offline state
C. Error state
D. All of the mentioned
Question 7
The signal, SLCT in the direction of signal flow, OUT, indicates the selection of
A. Control word register
B. CPU
C. Printer
D. Ports
Question 8
The signals that are provided to maintain proper data flow and synchronization between the data transmitter and receiver are
A. handshaking signals
B. control signals
C. input signals
D. none
Question 9
The strobed input/output mode is another name of
A. mode 0
B. mode 1
C. mode 2
D. none
Question 10
The pulse width of the signal INIT at the receiving terminal must be more than
A. 10 microseconds
B. 20 microseconds
C. 40 microseconds
D. 50 microseconds