Embedded System Applications REVIEW QUESTIONS
1.
The ADC module inside the PIC microcontroller used to convert analogue signal from temperature sensor LM35. If the Vref (+) of the ADC module is taken from an external source. Sketch a simple circuit to interface temperature sensor LM35 with PIC microcontroller.
2.
A PIC18 is connected to the 10 MHz crystal oscillator. Calculate the conversion time for the following options:
3.
a.
Fosc/32
b.
Fosc/16
A temperature sensor LM35 uses to detect an environment temperature. The output from the sensor is 10mV/ ΒΊC. The sensor is connected to the PIC18F4550 as shown in Figure 6.11. The 10-bit ADC module in the PIC18F4550 is configured to use VREF(+) = Vdd, VREF(-)= Vss. Assume Vdd = 5V and Vss = 0V. Calculate the digital output, if the environment temperature is 32 ΒΊC
Figure 6.11 4. An ADC module inside a PIC microcontroller is used to convert analogue signals from Maxsonar ultrasonic sensors. The specification analogue output from the sensor is illustrated in Figure 6.12. Calculate Digital Output, if sensor detect 10 cm in front of sensor if the ADC module is used with following setting:
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