Embedded System Peripheral MCQ Quiz – Objective Question with Answer for Embedded System Peripheral

The parallel port can transfer multiple bits of data simultaneously. It provides the input or output binary data with a single bit allocated to each pin within the port.

The LEDs, alphanumeric displays, and seven-segment displays are interfaced for the output whereas the switch is an input port.

The keyboards, switches, and knobs are used as output whereas the LEDs are used as the input port.

The basic operation of the parallel port deals with two types of registers which are called the data direction register and the data register.

The progression in the parallel ports provides a third register or an individual control bit which can make the pin in a high impedance state. An output port that can do this is also known as tri-state, that is, logic high, logic low, and a high impedance state.

The implementation of a parallel port uses a couple of buffers which are enabled by the data direction register by setting the corresponding bit of the register.

The register which offers high impedance is the individual control bit or the third register which can be implemented by switching off both the buffers and putting their connections to the pin which offers high impedance.

The multifunction I/O port can also be used as a chip select for the memory design. The function that the pin performs is set up internally through the use of a function register which internally configures how the external pins are connected internally.

The I/O port needs an external pull-up resistor. In some devices, it offers internally. If it is not provided, it can cause incorrect data on reading the port and it prevents the port from turning off an external device.

The multifunction I/O ports can be described as general-purpose and can be shared with other peripherals.

The embedded systems have a timing component called timer or counter which helps in the timing reference for control sequence, provides system tick for the operating system, and also helps in the generation of waveforms for the serial port baud rate generation.

The pre-scaler value determines the lowest frequency that can be generated from a given clock input. Actually, the bit size is determined by the pre-scalar value and the counter size.

The bit size is basically determined by its fundamental properties, that is, the pre-scalar value and the counter size. The counter size determines the maximum value of the counter-derived period.

The Intel 8253 timer is suitable for the IBM PC. IA-32 and Intel 64 are the offload timers used only for Intel. The 8051 timers are used for the timing program in 8051.

The interrupt on the terminal count is known as mode 0 for the 8253. An initial value is loaded into the count register and then starts to count down at the frequency which is determined by the clock input. When the count reaches zero, an interrupt is generated.