12. Output devices¶

Determining power consumption of an output device¶

For simulate that determination power consumption I used Tinkercad. The multimeter has to be connected in the following way to determinate a RGB power consumption:

I tried with two outputs also:

Applying the folowing formula I can calculate de Power consumption of the two outputs:

P = V*I = V^2/R = I^2 * R

Irgb = 18.1 mA
Icc= 79.9 mA

Vrgb=989 mV
Vcc =2.01V

Vrgb + Vcc = 2.99 V
Irgb + Icc = 98.0 mA

P = 2.99 * 0.098 = 0.293 W

I noticed that when I want to mesure voltage outputs turn to off.

Interfacing output devices to microcontroller¶

Te most important learning here was the relation between the micro-controller’s pins and the output. In my case , the outputs are a RGB and a buzzer. For this board I am usign a Attiny44 microcontroller (datasheet]) To interface an output device to this microcontroller I should use a bidirectional digital port.

Design and fabrication process¶

Previous design process example

Previous fabrication process example

I basically follow the same design process of the previous boards:

Importing components in the Schematics
Making the connections between pin’s

Designing 15 mil lines in the BRD work table

Exporting the design as a png image

creating a profile for the board

exporting a new png image
making a full white shape of that profile

Programming process¶

Fist I caracterized a variable for the buzzer’s pin.

int buzzer = A0;

After I set the pins configuration and the initial state of each pin.

void setup()
{
  pinMode(3,OUTPUT);//RED
  pinMode(2,OUTPUT);//BLUE
  pinMode(1,OUTPUT);//GREEN   PIN CONFIGURATION 
  pinMode(8, OUTPUT);
  pinMode(A7,OUTPUT);
  pinMode(buzzer,OUTPUT);
  digitalWrite(3,LOW);
  digitalWrite(2,LOW);
  digitalWrite(1,LOW);
  digitalWrite(8,LOW);
  digitalWrite(7,LOW);
  digitalWrite(buzzer,LOW);
}

After that I programmed the action of each pin

void loop() 
{
  digitalWrite(3,HIGH);
  delay(500);
  digitalWrite(3,LOW);
  delay(500);
  digitalWrite(2,HIGH);
  delay(500);
  digitalWrite(2,LOW);
  delay(500);
  digitalWrite(1,HIGH);
  delay(500);
  digitalWrite(1,LOW);
  delay(500);
  tone(buzzer,40,500);
  noTone(buzzer);
  }

Simulations¶

RGB simulation

Problems¶

I designed a first borad 1 before the pandemic for this assigment but I couldn’t fabricate it so when I wanted to make it I didn’t remendered one of the components I wanted to put as an output.
After that I designed a board 2 with and RGB as an output but my tutor told me it was to much simple.
Finally I designed the board 3 in wich I put a RGB and a buzzer.
I writed a program for my 2 outputs. In the simulation it worked or the rgb but not for the buzzer.

Original design files and code¶

Hero shot¶

Led video

The buzzer need a resistor

Buzzer video

Learning outcomes¶

[x] Demonstrate workflows used in controlling an output device(s) with MCU board you have designed

Have you?¶

[x]Linked to the group assignment page
[x]Documented how you determined power consumption of an output device with your group
[x]Documented what you learned from interfacing output device(s) to microcontroller and controlling the device(s)
[x]Described your design and fabrication process or linked to previous examples.
[x]Explained the programming process/es you used
[x]Outlined problems and how you fixed them
[x]Included original design files and code
[x]Included a ‘hero shot/video’ of your board