ATtiny (also known as TinyAVR) are a subfamily of the popular 8-bit AVR microcontrollers, which typically has fewer features, fewer I/O pins, and less memory than other AVR series chips. The first set of series were released in 1999 by ATMEL, later acquired by Microchip in 2016. This data is taken from ATMEL.

Prof. Neil was mentioning about Charlieplexing and Multiplexing during the session this week.

Charlieplexing is a technique for driving a multiplexed display in which relatively few I/O pins on a microcontroller are used e.g. to drive an array of LEDs. The method uses the tri-state logic capabilities of microcontrollers in order to gain efficiency over traditional multiplexing.
Multiplexing (or muxing) is a way of sending multiple signals or streams of information over a communications link at the same time in the form of a single, complex signal; the receiver recovers the separate signals, a process called demultiplexing (or demuxing). Bitwise Operations is an operator used to perform bitwise operations on bit patterns or binary numerals that involve the manipulation of individual bits, similar to logic operators.
I went through these diagrams for getting an idea about this week’s assignment. In this picture it shows ATTiny 85 is controlling the temperature. When the temperature goes down, the fan turns off. When the temperature goes high, the fan turns on. So I have used the same principle. But to control the fan, I am using a Relay Module 12v to control the fan to be used in my final project, Smart FAB air cooler.
Ideation – My Mind Mapping

Relay Module – A relay is an electrically operated switch that can be turned on or off, letting the current go through or not, and can be controlled with low voltages, like the 5V provided by the Arduino pins. I have used this One Channel Relay Module to control a 12v DC Fan in my final project.

Testing Video - Assignment 12 Output Device_files\input output devices.AVI
PCBI have milled and soldered a new pcb for the Input and Output Assignment as shown below.

PCB Milling Video – https://youtu.be/ua7fWLVYzR4
Design file – Assignment 12 Output Device_files\in and out.brd

Code-

int sensorPin = PB4;
int ledPin1 = PB3;
//int ledPin2 = 4;
int sensorValue = 0;
float volts=0.0,temp=0.0;
void setup() {
pinMode(ledPin1, OUTPUT);
//pinMode(ledPin2, OUTPUT);
//Serial.begin(9600);
}
void loop() {
sensorValue = analogRead(sensorPin);
volts= sensorValue*5.0/1023;
temp = volts*100;
//Serial.print("Temprature is");
//Serial.print(temp);
if(temp > 30) {
digitalWrite(ledPin1,HIGH);
//digitalWrite(ledPin2,LOW);
}
else {
//digitalWrite(ledPin2,HIGH);
digitalWrite(ledPin1,LOW);
}
delay(100);
}

My code for this assignment shows that when the temperature goes up, the LED turns off and when the temperature is medium the LED turns on.
Video Link


Group Assignment – I have teamed up with Jaydip for this group assignment.

I have used this PCB for testing as I did have a through hole component.
The LED is off as the temperature is cold.

Learning Outcome – I learnt how to put output on the pcb. The difficulty faced was rendering the blue tooth module to my pcb.

Reference – FAB Academy Tutorials, Internet and Wikipedia
http://fab.cba.mit.edu/classes/863.09/people/ryan/week5/ATtiny44%20Data%20Sheet.pdf
http://fab.cba.mit.edu/classes/863.17/CBA/people/annawb/week9.html
http://archive.fabacademy.org/2018/labs/fablabcept/students/rutuja-patel/13-output-devices.html
https://bigladdersoftware.com/epx/docs/8-3/input-output-reference/group-fans.html#inputs