A
Arduino•6d ago
Robo_17

how to attachinterrupt()

so i was trying to attach a interrupt to a pin(18) on arduino mega 2560 R3 and i wrote this code so i want the cursor to display a character and blink its like a typing system .The interrupt is not given response by the microcontroller i dont see any character blinking also i have double-checked the wiring this is the code -
6 Replies
Robo_17
Robo_17OP•6d ago
#include <LiquidCrystal.h>
#include <string.h>
const int rs =12,en=11,d4=5,d5=4,d6=3,d7=2;
int A,B,C,D,E,H,L = 0x0;
//int S,Z,AC,Carry
int flags[4] = {0,0,0,0};
//memory array
int memory[60] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
LiquidCrystal lcd(rs,en,d4,d5,d6,d7);
//push button,execute,enter
int pushButton = 18;
int execute = 19;
//int enter = ;
///////////////////////////
int executeState = 0;
int enterState = 0;
//always high pin
int alwayshigh = 34;

//The array of states
int state = 1; //this is needed to take input from user using the push button
int states[2] = {0,1};//1=Write,0=Read

//the array for characters to take input
char instructionChars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,";
char currentCharacter = 'A';
/////////////////////////////////////////////////////
#include <LiquidCrystal.h>
#include <string.h>
const int rs =12,en=11,d4=5,d5=4,d6=3,d7=2;
int A,B,C,D,E,H,L = 0x0;
//int S,Z,AC,Carry
int flags[4] = {0,0,0,0};
//memory array
int memory[60] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
LiquidCrystal lcd(rs,en,d4,d5,d6,d7);
//push button,execute,enter
int pushButton = 18;
int execute = 19;
//int enter = ;
///////////////////////////
int executeState = 0;
int enterState = 0;
//always high pin
int alwayshigh = 34;

//The array of states
int state = 1; //this is needed to take input from user using the push button
int states[2] = {0,1};//1=Write,0=Read

//the array for characters to take input
char instructionChars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789,";
char currentCharacter = 'A';
/////////////////////////////////////////////////////
int currentCursor[] = {0,0};
void setup() {
  // put your setup code here, to run once:
  pinMode(pushButton,INPUT_PULLUP);
  pinMode(execute,INPUT);
//  pinMode(enter,INPUT);
  pinMode(alwayshigh,OUTPUT);
  digitalWrite(alwayshigh,HIGH);
  lcd.begin(16,2);
  lcd.print("8085 Simulator");
  delay(2000);
  lcd.clear();
  lcd.setCursor(6,0);
  attachInterrupt(digitalPinToInterrupt(pushButton), changecharacter, RISING);
  for(int i =0;i<=3;i++){
    lcd.print(flags[i]);
  }
  lcd.setCursor(16,1);
  currentCursor[0] = 16;
}

//The ISR of the pushbutton
void changecharacter(){
  for(int i=0;i<=36;i++){
    if (instructionChars[i] == currentCharacter){
      currentCharacter = instructionChars[i];
      break;
    }
  currentCursor[0] -= 1;
  }
  delay(500);
}
///////////////////////////////

//The ISR of the the execute
// void executefunction(){
  
//   delay(100);
// }
//////////////////////////////////
//The ISR of enter
// void enter(){

// }
int blinkingCharacter(char character,int x,int y){
  while(enterState == 0){
    lcd.setCursor(x,y);
    lcd.print(character);
    delay(1000);
    lcd.print(" ");
  }
  return 0;
}
void loop() {
  // put your main code here, to run repeatedly:
  // lcd.setCursor(0,1);
  // lcd.print(millis()/1000);
  // delay(100);
  switch(state){
    case 1:
      blinkingCharacter(currentCharacter,currentCursor[0],currentCursor[1]);
  }
}
int currentCursor[] = {0,0};
void setup() {
  // put your setup code here, to run once:
  pinMode(pushButton,INPUT_PULLUP);
  pinMode(execute,INPUT);
//  pinMode(enter,INPUT);
  pinMode(alwayshigh,OUTPUT);
  digitalWrite(alwayshigh,HIGH);
  lcd.begin(16,2);
  lcd.print("8085 Simulator");
  delay(2000);
  lcd.clear();
  lcd.setCursor(6,0);
  attachInterrupt(digitalPinToInterrupt(pushButton), changecharacter, RISING);
  for(int i =0;i<=3;i++){
    lcd.print(flags[i]);
  }
  lcd.setCursor(16,1);
  currentCursor[0] = 16;
}

//The ISR of the pushbutton
void changecharacter(){
  for(int i=0;i<=36;i++){
    if (instructionChars[i] == currentCharacter){
      currentCharacter = instructionChars[i];
      break;
    }
  currentCursor[0] -= 1;
  }
  delay(500);
}
///////////////////////////////

//The ISR of the the execute
// void executefunction(){
  
//   delay(100);
// }
//////////////////////////////////
//The ISR of enter
// void enter(){

// }
int blinkingCharacter(char character,int x,int y){
  while(enterState == 0){
    lcd.setCursor(x,y);
    lcd.print(character);
    delay(1000);
    lcd.print(" ");
  }
  return 0;
}
void loop() {
  // put your main code here, to run repeatedly:
  // lcd.setCursor(0,1);
  // lcd.print(millis()/1000);
  // delay(100);
  switch(state){
    case 1:
      blinkingCharacter(currentCharacter,currentCursor[0],currentCursor[1]);
  }
}
note i replaced the pushbutton with a jumper wire and just make it high and low from +5V
DarwinWasW
DarwinWasW•6d ago
https://wokwi.com/projects/432368632038042625 works with a led - may be too much in ISR
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Robo_17
Robo_17OP•6d ago
hmn will test
DarwinWasW
DarwinWasW•6d ago
With ISR, you use volatile variables and just change a Boolean for the process to occur in the loop. doing a for loop and a delay will result in drama
Robo_17
Robo_17OP•6d ago
Actually i want to just change the currentchar value to the next character in the string so ig i will just keep a track of the currentchar index in that string outside isr
DarwinWasW
DarwinWasW•5d ago
Remember to use volatile on variables changed in ISR That are used else where.

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