1. High speed USB devices neglect a. Handshake packet b. Token packet c. PRE packet d. Data packet Ans- c. PRE packet 2. The bit packet that commands the device either to receive data or transmit data in transmission of USB async…
1. Which of the following is not a mode of data transmission? a. simplex b. duplex c. semi duplex d. half duplex Ans- c. semi duplex 2. If any change in sensor value is detected at the end of a sensor matrix scan, then the IRQ l…
1. The registers that store the keyboard and display modes and operations programmed by CPU are a. I/O control and data buffers b. Control and timing registers c. Return buffers d. Display address registers Ans- b. Control and t…
1. The control word register contents are used for a. initializing the operating modes b. selection of counters c. choosing binary/BCD counters d. all of the mentioned Ans- d. all of the mentioned 2. The counter starts counting …
1. The Isolation transformers are generally used for a. protecting low power circuit b. isolation c. protecting low power circuit and isolation d. none Ans- c. protecting low power circuit and isolation 2. The firing angles of t…
1. The pin that clears the control word register of 8255 when enabled is a. CLEAR b. SET c. RESET d. CLK Ans- c. RESET 2. The function, 'data bus tristated' is performed when a. CS(active low) = 1 b. CS(active low) = 0 c…
1. If 'n' denotes the number of rows that are to be refreshed in a single refresh interval, 'td' denotes the range of time it may take then, refresh time (tr) can be defined as a. n*td b. td/n c. n/td d. tdn Ans-…
1. In memory-mapped scheme, the devices are viewed as a. distinct I/O devices b. memory locations c. only input devices d. only output devices Ans- b. memory locations 2. In 74LS245, if DIR is 1, then the direction is from a. in…
1. In the signal integrate phase, the differential input voltage between IN LO(input low) and IN HI(input high) pins is integrated by the internal integrator for a fixed period of a. 256 clock cycles b. 1024 clock cycles c. 2048…
1. 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 Ans- d. all of the mentioned 2. The signals …
