UNIT 2

1. Which of the following is the correct syntax for setting a specific bit in an I/O port register in embedded C?

• PORTx |= (1 << 3);

• PORTx &= ~(1 << 3);

• PORTx = (1 << 3);

• PORTx |= (1 << 0);

In embedded C programming, how do you clear a bit (set it to 0) in an I/O port register?

• PORTx |= (1 << 3);

• PORTx &= ~(1 << 3);

• PORTx = (1 << 3);

• PORTx ^= (1 << 3);

What is the result of the following code in embedded C: PORTB |= (1 << PB2);?

• It clears the bit 2 of PORTB.

• It sets the bit 2 of PORTB.

• It toggles the bit 2 of PORTB.

• It does nothing to PORTB.

In which I/O direction mode do the I/O pins act as input in a microcontroller?

• Output mode

• Input mode

• Floating mode

• Tri-state mode

What is the primary function of a Timer/Counter in embedded systems?

• To generate PWM signals.

• To create delays and manage timing events.

• To control the direction of data flow in I/O ports.

• To perform analog-to-digital conversions.

n embedded C, to set the value of the timer for a 1-second delay with an 8-bit timer, assuming a 16 MHz clock and a prescaler of 256, the value of the timer register should be set to:

• 0x00

• 0xF4

• 0x02

• 0xFF

How do you stop the Timer in most embedded systems?

• Set the timer's prescaler to zero.

• Clear the timer enable bit.

• Reset the timer register.

• Disable the interrupt associated with the timer.

In Timer/Counter programming, what is the effect of setting the prescaler value?

• It increases the speed of the timer.

• It decreases the frequency of the timer.

• It enables the interrupt for the timer.

• It resets the timer value.

The delay calculation for a microcontroller timer depends on all of the following except:

• Clock frequency

• Prescaler value

• Timer mode

• Port direction mode

Which register is typically used for setting the value of a timer in embedded systems?

• PORT Register

• DDR Register

• TCNT Register

• PIN Register