8251 USART MCQs : This section focuses on the "8251 USART". These Multiple Choice Questions (MCQs) should be practiced to improve the 8251 USART skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
High speed USB devices neglect
A. Handshake packet
B. Token packet
C. PRE packet
D. Data packet
Question 2
If the data is transmitted only in one direction over a single communication channel, then it is of
A. simplex mode
B. duplex mode
C. semi duplex mode
D. half duplex mode
Question 3
If the data transmission takes place in either direction, but at a time data may be transmitted only in one direction then, it is of
A. simplex mode
B. duplex mode
C. semi duplex mode
D. half duplex mode
Question 4
In 8251A, the pin that controls the rate at which the character is to be transmitted is
A. TXC(active low)
B. TXC(active high)
C. TXD(active low)
D. RXC(active low)
Question 5
The bit packet that commands the device either to receive data or transmit data in transmission of USB asynchronous communication is
A. Handshake packet
B. Token packet
C. PRE packet
D. Data packet
Question 6
The disadvantage of RS-232C is
A. limited speed of communication
B. high-voltage level signaling
C. big-size communication adapters
D. all of the mentioned
Question 7
The signal that may be used either to interrupt the CPU or polled by the CPU is
A. TXRDY(Transmitter ready)
B. RXRDY(Receiver ready output)
C. DSR(active low)
D. DTR(active low)
Question 8
The USB supports the signaling rate of
A. full-speed USB 1.0 at rate of 12 Mbps
B. high-speed USB 2.0 at rate of 480 Mbps
C. super-speed USB 3.0 at rate of 596 Mbps
D. all of the mentioned
Question 9
TXD(Transmitted Data Output) pin carries serial stream of the transmitted data bits along with
A. start bit
B. stop bit
C. parity bit
D. all of the mentioned
Question 10
Which of the following is not a mode of data transmission?
A. simplex
B. duplex
C. semi duplex
D. half duplex