if statement within a switch case??

system · July 8, 2014, 5:14pm

Hi guys,

Is it possible to have an if statement within a switch case for example:

  switch(counter)
  {
    case 0:
      mainMenu();
      time();
      break;      
    case 1:
      lcd.setCursor(0,1);
      lcd.write(Symbol_2);
        lcd.setCursor(0,2);
        lcd.write(Symbol_1);
          lcd.setCursor(0,3);
          lcd.write(Symbol_1);
            lcd.setCursor(10,1);
            lcd.write(Symbol_1);
            break;
    case 2:
      if (counter == 1)
      {
          delay(300);
          lcd.clear();
          pumpStatus("Pump One");
       }
       break;
  }

system · July 8, 2014, 5:17pm

Is it possible to have an if statement within a switch case

Yes. But, if the switch statement case selected case 2 because counter contained 2, then the likelihood of counter equaling 1 is pretty slim.

system · July 8, 2014, 5:18pm

and the curly braces would be as shown?

system · July 8, 2014, 5:19pm

Junblud:
and the curly braces would be as shown?

Yes, but the if statement will never be true.

system · July 8, 2014, 7:21pm

yes i am experiencing what you said. Maybe i think the answer is another counter? so how do i stop the first counter and start another? hmm?

thanks for your help!

this is what i have so far:

#include <Wire.h>
#include "RTClib.h"
RTC_DS1307 RTC;
#include <TimeAlarms.h>
#include <Time.h>
#include <LiquidCrystal.h>
#include <SPI.h>

LiquidCrystal lcd(12,11,5,4,3,2);
int backLight = 10;
const int latchPin = 8;
const int dataPin = 9;
const int clockPin = 7;

byte switchVar = B00000000;
byte counter = 0;
byte SymbolPosition = 5;

const int numRows = 4;
const int numCols = 20;
const byte Symbol_1 = B10110000;
const byte Symbol_2 = B01111110;

/*Switch Binary Code Reference (in order according to breadboard)
32 == Down
64 == Up 
129 == Right
2 == left
4 == Options 
8 == Ok
16 == Back
*/

void setup()
{
  pinMode (backLight, OUTPUT);
  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(dataPin, INPUT);
  
  //RTC boot up
  Wire.begin();
  RTC.begin();
  
//lcd boot up screen
  digitalWrite(backLight, HIGH);
  lcd.begin(numCols,numRows);
  lcd.setCursor(6,0);
  lcd.print("WELCOME");
  lcd.setCursor(1,1);
  lcd.print("Dosing Pump Module");
  lcd.setCursor(5,2);
  lcd.print("By JUNBLUD");
  lcd.setCursor(4,3);
  lcd.print("Loading:");
  for (int i = 0; i <= 100; i++)
  {
    lcd.setCursor(12,3);
    if (i<100) lcd.print(" "); 
    if (i<10) lcd.print(" ");
    lcd.print(i);
    lcd.print("%");
    delay(100); 
  }
   delay(2000);
   lcd.clear();
}

void time ()
{
  DateTime now = RTC.now();
  lcd.setCursor(12,0);
  lcd.print(now.hour(), DEC);
  lcd.print(':');
  lcd.print(now.minute(), DEC);
  lcd.print(':');
  lcd.print(now.second(), DEC);
}

void mainMenu()
{
  lcd.setCursor(0,0);
  lcd.print("Main Menu");
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("Pump 1");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("Pump 2");
         lcd.setCursor(0,3);
         lcd.write(Symbol_1);
         lcd.setCursor(2,3);
         lcd.print("Set Schedule");
           lcd.setCursor(10,1);
           lcd.write(Symbol_1);
           lcd.setCursor(12,1);
           lcd.print("Pump 3");
}

void pumpStatus(const char *pumpStatusNum)
{
  lcd.setCursor(0,0);
  lcd.print(pumpStatusNum);
   lcd.setCursor(2,1);
   lcd.print("Dosage 1 =");
     lcd.setCursor(13,1);
     lcd.print("00:00");
       lcd.setCursor(2,2);
       lcd.print("Dosage 2 =");
       lcd.setCursor(13,2);
       lcd.print("00:00");
}

void setScheduleMenu()
{
   lcd.setCursor(0,0);
   lcd.print("Set Schedule");
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("Pump 1");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("Pump 2");
         lcd.setCursor(0,3);
         lcd.write(Symbol_1);
         lcd.setCursor(2,3);
         lcd.print("Pump 3");
}

void adjustPump(const char *adjustPumpNum)
{
   lcd.setCursor(0,0);
   lcd.print(adjustPumpNum);
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("Everyday at");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("everyday at");
         lcd.setCursor(0,3);
         lcd.write(Symbol_1);
         lcd.setCursor(2,3);
         lcd.print("Amount 000ml");
}

void options()
{
  lcd.setCursor(0,0);
  lcd.print("Options");
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("Pump Flush");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("Manual Dose");
       lcd.setCursor(0,3);
       lcd.write(Symbol_1);
       lcd.setCursor(2,3);
       lcd.print("Schedule Reminder");
}

void pumpFlush()
{
   lcd.setCursor(0,0);
   lcd.print("Pump Flush");
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("Flush Pump 1");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("Flush Pump 2");
         lcd.setCursor(0,3);
         lcd.write(Symbol_1);
         lcd.setCursor(2,3);
         lcd.print("Flush Pump 3");
}

void scheduleReminder()
{
  lcd.setCursor(0,0);
   lcd.print("fist line goes here");
     lcd.setCursor(0,1);
     lcd.write(Symbol_1);
     lcd.setCursor(2,1);
     lcd.print("second line goes here");
       lcd.setCursor(0,2);
       lcd.write(Symbol_1);
       lcd.setCursor(2,2);
       lcd.print("third line goes here");
         lcd.setCursor(0,3);
         lcd.write(Symbol_1);
         lcd.setCursor(2,3);
         lcd.print("forth line goes here");
}

void shiftRegister()
{
  digitalWrite(backLight, HIGH);
  
  digitalWrite(latchPin, HIGH);
  delayMicroseconds(20);
  digitalWrite(latchPin, LOW);

  switchVar = shiftIn(dataPin, clockPin, MSBFIRST);
}

void loop()
{
  while (counter == 0,1,2,3,4,5)
  {
    shiftRegister();
    if(switchVar == 32)
    {
      delay(300);
      counter+1 < SymbolPosition? counter++ : counter = 1;
    }
    shiftRegister();
    if (switchVar == 64)
    {
      delay(300);
      counter-1 > 0? counter--: counter = SymbolPosition-1;
    }
    switch(counter)
    {
      case 0:
        mainMenu();
        time();
        break;      
      case 1:
        lcd.setCursor(0,1);
        lcd.write(Symbol_2);
          lcd.setCursor(0,2);
          lcd.write(Symbol_1);
            lcd.setCursor(0,3);
            lcd.write(Symbol_1);
              lcd.setCursor(10,1);
              lcd.write(Symbol_1);
              break;
      case 2:
        lcd.setCursor(0,1);
        lcd.write(Symbol_1);
          lcd.setCursor(0,2);
          lcd.write(Symbol_2);
            lcd.setCursor(0,3);
            lcd.write(Symbol_1);
              lcd.setCursor(10,1);
              lcd.write(Symbol_1);
              break;      
      case 3:
        lcd.setCursor(0,1);
        lcd.write(Symbol_1);
          lcd.setCursor(0,2);
          lcd.write(Symbol_1);
            lcd.setCursor(0,3);
            lcd.write(Symbol_2);
              lcd.setCursor(10,1);
              lcd.write(Symbol_1);
              break;   
      case 4:
        lcd.setCursor(0,1);
        lcd.write(Symbol_1);
          lcd.setCursor(0,2);
          lcd.write(Symbol_1);
            lcd.setCursor(0,3);
            lcd.write(Symbol_1);
              lcd.setCursor(10,1);
              lcd.write(Symbol_2);
              break;
      case 5:
        lcd.setCursor(0,1);
        lcd.write(Symbol_2);
          lcd.setCursor(0,2);
          lcd.write(Symbol_1);
          break;
      case 6:
        lcd.setCursor(0,1);
        lcd.write(Symbol_1);
          lcd.setCursor(0,2);
          lcd.write(Symbol_2);
          break;
    }
    {
      if (counter == 1 && switchVar == 8)
      {
        delay(300);
        counter = 5;
        lcd.clear();
        pumpStatus("Pump One");
        {
          if (switchVar == 32 && counter == 5)
          {
            counter = 6;
          }
        }
      }
      if (counter == 2 && switchVar == 8)
      {
        delay(300);
        lcd.clear();
        pumpStatus("Pump Two");
      }
      if (counter == 3 && switchVar == 8)
      {
        delay(300);
        lcd.clear();
        setScheduleMenu();
      }
      if (counter == 4 && switchVar == 8)
      {
        delay(300);
        lcd.clear();
        pumpStatus("Pump Three");
      }
      if (switchVar == 16)
      {
        delay(300);
        lcd.clear();
        counter = 0;
      }
      if (switchVar == 4)
      {
        delay(300);
        lcd.clear();
        options();
      }
    }
  }
}

system · July 8, 2014, 7:50pm

Maybe i think the answer is another counter? so how do i stop the first counter and start another? hmm?

That would
depend to a
large extent on
what you are counting.

Why
does
your
code
keep
creeping
across
the
screen?

system · July 8, 2014, 8:52pm

well i want to count to 5 and down again which is shown here

{
  shiftRegister();
  if(switchVar == 32)
  {
    delay(300);
    counter+1 < SymbolPosition? counter++ : counter = 1;
  }
  shiftRegister();
  if (switchVar == 64)
  {
    delay(300);
    counter-1 > 0? counter--: counter = SymbolPosition-1;
  }

now i want to stop that counter and start another here which counts up to three.

the problem is that i want to use the shift registers outputs again i.e. 32 and 64 with another counter as well as the above counter. as it is in a loop there is confusion between each counter when the shift register reads 32 and 64

Im not sure, i think it helps me to read it better.

system · July 8, 2014, 9:06pm

well i want to count to 5 and down again which is shown here

Count what? Are watermelons rolling by? One does not just count for the hell of it. One counts events, and uses a variable name that reflects the event being counted.

Meaningful names would go a long ways towards making your code better. I can guess, with a reasonable degree of certainty, what digitalRead() does. I haven't a clue what shiftRegister() does.

system · July 8, 2014, 9:14pm

shiftregister()
is a function called upon from void setup.

facetious much!?/ read my whole code post

i am using meaningful names! shiftregister is a function i created that tells the arduino to read what binary code the shiftregister is sending

i'm not specifically counting anything, but how many times a button is pressed. i.e. if x button is pressed +1, if y button is pressed -1.

is it not possible to stop one counter and start another?

michinyon · July 8, 2014, 9:16pm

Sure. Why not ?

But if you want two different variables to count , you have to give them different names.

system · July 8, 2014, 9:18pm

ive tried doing that but becasue the +1 and -1 is coming from the same buttons from the shiftregister, is gets confused as to which counter is to be added too or subtracted

system · July 8, 2014, 9:23pm

shiftregister()
is a function called upon from void setup.

I know it's a function, and I can see that it is called from setup(). However, digitalRead(), which reads from a digital pin, isn't called digital(). The name tells us exactly what the function does. shiftRegister() doesn't. A shift register is a piece of hardware that can be read from or written to. A name like readShiftRegister() or writeShiftRegister() would tell us more.

i am using meaningful names!

You are NOT. counter? shiftRegister()? Don't make me laugh. Neither of these names means squat.

michinyon · July 8, 2014, 9:27pm

It's not getting confused. You are.

system · July 8, 2014, 9:39pm

ok ive fixed that.

now, whilst using the same variables from the shift register how do i get them to control two different counters.

what i am trying to achieve is a lcd menu where you can scroll up and down. due to there being less options to select in the sub menu i need a different counter. there are 5 different options in the main menu and in the sub menu there are 2.

when the sub menu is selected i need to stop the main menu counter and start the sub menu counter

Arrch · July 8, 2014, 9:45pm

Junblud:
when the sub menu is selected i need to stop the main menu counter and start the sub menu counter

So you need some type of state variable to keep track of what menu you are on:

enum { MAIN_MENU, SUB_MENU1, SUB_MENU2 } myLCDState = MAIN_MENU;
...
switch (myLCDState )
{
  case MAIN_MENU:
    mainMenuCounter++;
    break;
  case SUB_MENU1:
    subMenu1Counter++;
    break;
  case SUB_MENU2:
    subMenu2Counter++;
    break;
}

Then you can set myLCDState when you change menus.

system · July 8, 2014, 9:56pm

indeed, and the counter keeps track of the position of the menu selection.

so how to i integrate the two switch cases?

Arrch · July 8, 2014, 11:20pm

Junblud:
so how to i integrate the two switch cases?

By combining them in a way that makes the code do what you want it to do.

(General questions get general answers)

system · May 5, 2021, 8:46pm