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challenges/Embedded/tasks.md
2018-08-29 12:27:14 +05:30

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Task 1

Part (a)

A low-impedant sensor outputs a 100 Hz sine wave which has a peak-to-peak amplitude ranging from 10 mv to 100 mv (depending on the the parameter being sensed - ignore that for now). A 4.0 V DC offset is superimposed on this output

  1. Draw the input waveform
  2. Draw a circuit for extracting this sine wave and amplifying it so that it can be fed to a 8-bit ADC with Vref of 5V. Also draw the output of this circuit.

Note : You can provide hand-drawn design for this part. No need to provide part number for the op-amps and other electronic components but please label all components. A short explanation on the working of the circuit is expected.

Part(b)

Assuming that output of your circuit in part(a) is being fed to A0 pin of an Arduino, develop a program to :

  1. Convert the analog to a digital value with a conversion time satisfying Nyquist criteria. Name this function “measureADC”

  2. Accept the following two user inputs via COM port (at baud 9600): “w” to do one ADC conversion and write the value at location “0” of flash memory “r” to read the value at location “0” of flash memory The functions should be named “f_write”: and “f_read”

Note: Don't use open source library for read and write operations in flash memory in this.

Task2

Repeat part (a) of Task 1 but with the sensor being high-impedant (max current of 1 micro Amp). Everything else remains same. No need to repeat part (b)