1. GPS module like SIM900/800 uses which protocol?
a) UART protocol
b) USART protocol
c) SPI protocol
d) I2C protocol
Explanation: GSM/GPS modules like SIM900/800 uses UART communication for accepting AT commands that are used to control them and gather the replies.
2. Finger print sensor uses which interface?
a) USART protocol
b) UART protocol
c) SPI protocol
d) I2C protocol
Explanation: Projects that use RFID modules can be built with modules that have a UART interface. This even applies to some finger print sensors.
3. UART is similar to _________
a) SPI protocol
b) I2C protocol
c) HTTP protocol
d) MQTT protocol
Explanation: UART(Universal Asynchronous Receiver/Transmitter) is a small, efficient communication device, similar to I2C.
4. What does UART contain?
a) Parallel register
b) Shift register
c) Clock
d) Parallel shift register
Explanation: UART contains a shift register, which is the fundamental method of conversion between serial and parallel forms.
5. Communication in UART is ___________
a) Only simple
b) Only duplex
c) Only full duplex
d) Simplex, half duplex, full duplex
Explanation: Communication may be simplex(in one direction only no provision for the receiving device to send data back to the transmission device), full duplex(both devices send and receive data at the same time), half duplex(devices takes turns transmitting and receiving).
6. Which error occurs when the receiver can’t process the character?
a) Overrun error
b) Underrun error
c) Framing error
d) Break condition
Explanation: An over run error occur when the receiver cannot process the character that just came in before the next one arrives. If the CPU or DMA controller does not service the UART quickly enough and the buffer become full, an over run will occur, and incoming will be lost.
7. What is WD1402A?
a) SPI
b) USART
c) SPIUART
d) I2C
Explanation: WD1402A is the first single chip UART on general sale. Introduced about 1971. Compatible chip included the Fairchild TR1402A and the general instruments AY-5-1013.
8. Which error occurs when UART transmitter has completed sending a character and the transmit buffer is empty?
a) Overrun error
b) Underrun error
c) Framing error
d) Break condition
Explanation: An Under run error occurs when UART transmitter has completed sending a character and the transmit buffer is empty. In asynchronous mode this is treated as an indication that no data remains to be transmitted.
9. Which error occurs when the designated start and stop bits are not found?
a) Overrun error
b) Underrun error
c) Framing error
d) Break condition
Explanation: A framing error occurs when the designated start and stop bits are not found. If the data line is not in the expected state when the stop bit is expected, a framing error will occur.
10. Which error occurs when the parity of the number of 1 bit disagrees with that specified by the parity bit?
a) Overrun error
b) Underrun error
c) Framing error
d) Parity error
Explanation: A parity error occurs when the parity of the number of 1 bit disagrees with that specified by the parity bit. Using parity is optional, so this error will only occur if parity checking has been enabled.