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6. Electronics design


Group Assignment

  • Use the test equipment in your lab to observe the operation of a microcontroller circuit board (in minimum, check operating voltage on the board with multimeter or voltmeter and use oscilloscope to check noise of operating voltage and interpret a data signal)
  • Document your work to the group work page and reflect on your individual page what you learned

Individual Assignment

What I did this week

  1. Test the operation of a circuit board by multimeter and oscilloscope → in this page
  2. Design: Redraw the circuit board with botton and LED → Individual Page
  3. Check: Design Rule Check and make the circuit board → Individual Page
  4. Make: Assemble electronic components to the board → Individual Page
  5. Test: Write programme to the microcomputer on making breakout board → Individual Page

1. Test the operation of a circuit board by multimeter and oscilloscope

the board I used for test

3216 breakout board



Multimeter Test

A multimeter is an indispensable tool used to make various electrical measurements of which we are not able to see with our naked eyes without the aid of this valuable tool.

  • device we use
    • sanwa PM3


  • Test 1 :Measure Voltage between IC2 IN and GND


    • acquire the outcome of “5.18V” which is correct judging theoretically from the board


  • Test 2 : Measure Voltage between IC2 OUT and GND

    • acquire the outcome of “3.3V” which is correct judging theoretically from the board


  • Check soldering connections

    • change mode “beep”
    • soldered (Connected)
    • short (should not be connected, but connected)


  • it can also check whether LED illuminates or not


Oscilloscope Test

Oscilloscopes test and display voltage signals as waveforms, visual representations of the variation of voltage over time. The signals are plotted on a graph, which shows how the signal changes.

The oscilloscope we used

Tektronix TBS1052B



Before the test, first of all we should calibrate the probe precision.

  • manual probe compensation

Read Oscilloscope



Connect the probes to “probe compensation port”


prove > voltage >


create Echo.ino in arduino

void setup() {

void loop() {
if(Serial.available() > 0){



Connect the programmer to the tagrget circuit


Upload done

upload done

After reconnecting, check if serial communication can be undergo or not .

Note: Serial communication is a communication method that uses one or two transmission lines to send and receive data, and that data is continuously sent and received one bit at a time. Since it allows for connections with few signal wires, one of its merits is its ability to hold down on wiring material and relaying equipment costs. It is the most widely used approach to transfer information between data processing equipment and peripherals.

Open Serial monitor in Arduino and send “hello.”

Then, “hello” returns on the spot which means to work correctly “echo” programme. We were able to confirm that the program was written to the IC and serial communication was working without any problems.


Connect an adapter which has vertical ports for easy checking


Test voltage signals of Tx and Rx

Connect ports to oscilloscope

  • 1 channel (yellow) :Tx (Transmitter)
  • 2 chanel(blue) : Rx (Receiver)


when I typed “a”, oscilloscope showed the shape below


when I typed “U”, oscilloscope showed the shape below



the waveform told us the ammont of voltage below.

  • Tx ΔV = 3.36V
  • Rx ΔV=5.28V


Zoom in and measure the time, a single width shows 8.5μs.


the number of signals is set 115200 per 1 second in arduino, which is calculated 8.68μs per 1 signal. It means that the oscilloscope results and theoretical values were in agreement.

send “yukiya” of my name and check its waveform


→This is the shape of me in mini computer

Reconnect to Probe RX line and conduct 2 types of test.

Test1 : test 3.3V regulator works well or not


  • yellow : Voltage from USB by Prove1 (in theory 5V) -> actually 5.52V

  • blue : Voltage after regulator from USB by Prove2 (n theory 3.3V) -> actually 3.84V


This is why I could check 3.3V regulator working well (though it was just a little off the theoretical value).

Test2 : test 4.99k Resistor drops voltage or not

test2_before_and _after_4.99k.png

  • yellow : Voltage from RX pin from 3216 by Prove1 (in theory 5V) -> actually 5.52V
  • blue : Voltage after 4.99k Resistor from USB by Prove2 (should be 3.3V because SAMD11 works on its voltage) -> actually 3.84V


We see that 5.52 - 3.84 = 1.68V drop due to the 4.99k resistor This is why I could check 4.99k resistor working well.

What we learn this week

to Individual Page

Last update: June 25, 2022