Embedded Programming

Reprogramming the Recreated echo hello-world Board

Basic Programming

For this week I attempted to program something based off of the inital C code that Neil provided but avrc and pin changes had a high learning curve, so I ended up programming my board using the Arduino IDE to take away some of the complexity. First I needed to import my board into my IDE, I used the example from highlowtech to import this and understand which pins I needed to write and how they differed from my schematic. I initially started off very simply and just programmed my board to shine when the button was pressed with the following code:

const int BUTTON = 3; //button connected to attiny44 pin 3
const int LED = 2; //led connected to attiny44 pin 2

void setup() {
  pinMode(BUTTON, INPUT);
  pinMode(LED, OUTPUT);
}

void loop() {

  int buttonState = digitalRead(BUTTON);

  if(buttonState==HIGH){
    digitalWrite(LED, LOW);   // turn the LED off by making the voltage LOW
  }

  else{
    digitalWrite(LED, HIGH);    // turn the LED on (HIGH is the voltage level)
  }
}
    

and successfully programmed the board by selecting the board as the attiny44 and the programmer as the USBtiny ISP!

Higher Level Attempt

Building off of this initial code, I wanted to try doing something more advanced to utilize the button on the board. I thought it would be cool to program something that could interpret morse code and translate it it to a string of text it could output in a text file or even email to a designated email address using a mail client. Needless to say I did not get all of this done but would like to circle back to it given more time. I definitely struggled the most with the logic for the loop function and differentiating between when the pauses between button pushes corresponded to the end of a character vs the end of a word vs the end of the message (I did say being course 6-3 was subject to change). You can find my partially written very incorrect code below.

const int BUTTON = 10; //button connected to attiny44 pin 10
const int LED = 11; //led connected to attiny44 pin 11
int morse[5]; //morse code has max 5 dots or dashes
char message[200]; //max 200 char message
unsigned long messageEnd;
unsigned long dot;
unsigned long eom;
unsigned long cTime;
//morse dictionary maybe and just parse the array and look it up...
//need to figure out wtf you do for spaces just a pause I guess... or no spaces 
//yeah maybe no spaces this is way harder than I originally thought it would be. 
int index;
//need to redo the logic for all of this
void setup() {
  pinMode(BUTTON, INPUT);
  pinMode(LED, OUTPUT);
  cTime = millis();
  index=0;
}
void translateMorse(){
  //TODO
}
void loop() {
  int buttonState = digitalRead(BUTTON);
  unsigned long durationStill;
  unsigned long durationPressed;
  
  if(buttonState==HIGH){
    digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
    durationStill=millis()-cTime;
    cTime=millis();
    
  }
  else{
    digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
    durationPressed=millis()-cTime;
    cTime=millis();
    //logic wrong some things should be when the button is pressed
    if(durationStill>=eom&&message.size()>0){
        //basically complete the message translate the message and
        //email it?
        message=new char[200];
        index=0;
    }
    else if(durationStill<=eom&&durationStill<=charPause){
        //determine whether pressed was a dot or a dash
        if(durationPressed<=dot){
          morse[index]=0;
        }
        else{
          morse[index]=1;
        }
        index+=1;
    }
    else if(durationStill>=charPause){
        //here would want to say the specific  morse letter
        //has been spelled outtranslate and insertinto char message
        morse=new int[5];
    }
  }
}