4 digit 7 segment display help in code!

narzan · April 29, 2015, 11:56pm

look at comment #15 for the last update
~~I connect 4 digit 7 segment display to UNO-R3 like this~~
~~LED UNO~~
~~1 10~~
~~2 9~~
~~3 13~~
~~4 8~~
~~5 12~~
~~6 5~~
~~7 4~~
~~8 7~~
~~9 3~~
~~10 11~~
~~11 5~~
~~12 2~~
~~there is no datasheet for it, from my testing i made this map NOTE "always First numbers (-)"~~

~~and this is my code simple timer~~

//segments

int a = 2;
int b = 3;
int c = 9;
int d = 6;
int e = 7;
int f = 5;
int g = 10;
int p = 11;
//digits
int d4 = 4;
int d3 = 8;
int d2 = 12;
int d1 = 13;
//other
long n = 0;
int x = 100;
int del = 45;

void setup()
{
  pinMode(d1, OUTPUT);
  pinMode(d2, OUTPUT);
  pinMode(d3, OUTPUT);
  pinMode(d4, OUTPUT);
  pinMode(a, OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(p, OUTPUT);
}

void loop()
{
  clearLEDs();
  pickDigit(1);
  pickNumber((n/x/1000)%10);
  delayMicroseconds(del);
  
  clearLEDs();
  pickDigit(2);
  pickNumber((n/x/100)%10);
  delayMicroseconds(del);
  
  clearLEDs();
  pickDigit(3);
  dispDec(3);
  pickNumber((n/x/10)%10);
  delayMicroseconds(del);
  
  clearLEDs();
  pickDigit(4);
  pickNumber(n/x%10);
  delayMicroseconds(del);
  
  n++;
  
  if (digitalRead(13) == HIGH)
  {
    n = 0;
  }
}

void pickDigit(int x)
{
  digitalWrite(d1, LOW);
  digitalWrite(d2, LOW);
  digitalWrite(d3, LOW);
  digitalWrite(d4, LOW);
  
  switch(x)
  {
    case 1: digitalWrite(d1, HIGH); break;
    case 2: digitalWrite(d2, HIGH); break;
    case 3: digitalWrite(d3, HIGH); break;
    default: digitalWrite(d4, HIGH); break;
  }
}

void pickNumber(int x)
{
  switch(x)
  {
    default: zero(); break;
    case 1: one(); break;
    case 2: two(); break;
    case 3: three(); break;
    case 4: four(); break;
    case 5: five(); break;
    case 6: six(); break;
    case 7: seven(); break;
    case 8: eight(); break;
    case 9: nine(); break;
  }
}

void dispDec(int x)
{
  digitalWrite(p, LOW);
}

void clearLEDs()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(p, HIGH);
}

void zero()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, HIGH);
}

void one()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
}

void two()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, LOW);
}

void three()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, LOW);
}

void four()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
}

void five()
{
  digitalWrite(a, LOW);
  digitalWrite(b, HIGH);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, HIGH);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
}

void six()
{
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
}

void seven()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
}

void eight()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
}

void nine()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
}
}

~~My problem is it's only show weird characters!~~

anon57585045 · April 30, 2015, 12:09am

You never mapped the segments. For example, "a" is pin 11 on the module, you show it as going to pin 5 on the arduino. But you have designated pin 1 to "a" in software.

So you should have instead:

int a = 5;
int b = 2;
//...etc

Also, 45 microseconds per digit is too fast. You may get ghosting.

Your second problem is a big one (as stated anyway) You have a note that first numbers in your module chart are negative polarity for the applied voltage. That would imply a common cathode display. So all your program logic is inverted! Because for common cathode, an active digit is LOW and an active segment is HIGH. You have it the other way around.

narzan · April 30, 2015, 12:10am

sorry i made a mistake by uploading other code check it now

int a = 11;
int b = 12;
int c = 3;
int d = 2;
int e = 6;
int f = 7;
int g = 10;
int p = 11;
//digits
int d4 = 1;
int d3 = 4;
int d2 = 5;
int d1 = 7;

anon57585045 · April 30, 2015, 12:26am

narzan:
sorry i made a mistake by uploading other code check it now
int a = 11;

int b = 12;
int c = 3;
int d = 2;
int e = 6;
int f = 7;
int g = 10;
int p = 11;
//digits
int d4 = 1;
int d3 = 4;
int d2 = 5;
int d1 = 7;

Wrong. Those are the module pin numbers. The software doesn't care about those.

narzan · April 30, 2015, 12:31am

this is my first time, on this kind of display
by the way rotate that pic its upside down don't kill me

anon57585045 · April 30, 2015, 12:35am

narzan:
this is my first time, on this kind of display, don't kill me
ok i learn fast, tell me what i must change !

Killing you? I'm just telling you the facts. Just have a cup of coffee and look it over.

narzan · April 30, 2015, 12:38am

JK by the way the pic it's upside down, just rotate it to make D1 on the lift

anon57585045 · April 30, 2015, 12:41am

"by the way" it's totally wrong? Now you're cruising for a bruising.

... but it would then be:

int a = 9;
int b = 5;
//...etc

narzan · April 30, 2015, 12:47am

ok let me learn more about this kind of display, it seems i don't know how they work
and i will back, thanks aarg

anon57585045 · April 30, 2015, 12:52am

narzan:
ok let me learn more about this kind of display, it seems i don't know how they work
and i will back, thanks aarg

Try to consider the conditions to illuminate a particular segment first, like "a" of digit 0. What would it take? Then go from there...

Also, I hope you have current limiting resistors on all the segment lines?

narzan · April 30, 2015, 3:22am

finally 1 digit work i connect them like that
LED arduino
2 2
6 6
9 9
11 11
12 12
3 3
7 GND

it count from 0-9 but when it count 0 the forth digit work too not know why it same with 1,4,7

this is my code

int a = 2;
int b = 6;
int c = 9;
int d = 11;
int e = 12;
int f = 3;
int g = 8;


void setup() {               
  pinMode(a, OUTPUT);
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
}
void displayDigit(int digit)
{
 //Conditions for displaying segment a
 if(digit!=1 && digit != 4)
 digitalWrite(a,HIGH);
 
 //Conditions for displaying segment b
 if(digit != 5 && digit != 6)
 digitalWrite(b,HIGH);
 
 //Conditions for displaying segment c
 if(digit !=2)
 digitalWrite(c,HIGH);
 
 //Conditions for displaying segment d
 if(digit != 1 && digit !=4 && digit !=7)
 digitalWrite(d,HIGH);
 
 //Conditions for displaying segment e 
 if(digit == 2 || digit ==6 || digit == 8 || digit==0)
 digitalWrite(e,HIGH);
 
 //Conditions for displaying segment f
 if(digit != 1 && digit !=2 && digit!=3 && digit !=7)
 digitalWrite(f,HIGH);

 if (digit!=0 && digit!=1 && digit !=7)
 digitalWrite(g,HIGH);
 
}
void turnOff()
{
  digitalWrite(a,LOW);
  digitalWrite(b,LOW);
  digitalWrite(c,LOW);
  digitalWrite(d,LOW);
  digitalWrite(e,LOW);
  digitalWrite(f,LOW);
  digitalWrite(g,LOW);
}
void loop() {
  for(int i=0;i<10;i++)
 {
   displayDigit(i);
   delay(1000);
   turnOff();
 }
}

PaulMurrayCbr · April 30, 2015, 4:39am

void pickDigit(int x)
{  
  digitalWrite(d1, LOW);
  digitalWrite(d2, LOW);
  digitalWrite(d3, LOW);
  digitalWrite(d4, LOW);

  switch(x)
  {
    case 1: digitalWrite(d1, HIGH); break;
    case 2: digitalWrite(d2, HIGH); break;
    case 3: digitalWrite(d3, HIGH); break;
    default: digitalWrite(d4, HIGH); break;
  }
}

Shouldn't this be

void pickDigit(int x)
{
  clearLED();

  switch(x)
  {
    case 1: one(); break;
    case 2: two(); break;
    case 3: three(); break;
    default: four(); break;
  }
}

anon57585045 · April 30, 2015, 5:28am

narzan:
finally 1 digit work i connect them like that
LED arduino
2 2
6 6
9 9
11 11

Narz, Narz, Narz. How is that supposed to help? There is no rule that you have to connect the same number pin on the module as on the Arduino. The numbers are just made up by the hardware designers anyway. It's not very helpful unless you can easily connect all of them in some logical sequence. But the display connections don't follow any useful pattern.

...and you DO have current limiting resistors on all the segments, yes?

narzan · April 30, 2015, 5:39am

i though that's maybe will help
and actually work! but i don't know why the fourth digit work when display show these numbers 0,1,4,7
only if i put a resistor, if i remove it, and connect 7 to GND directly there is no issues but that's not safe
your idea to focus on 1 digit work thanks
i will go to sleep i see numbers everywhere......

anon57585045 · April 30, 2015, 7:01am

narzan:
i though that's maybe will help
and actually work! but i don't know why the fourth digit work when display show these numbers 0,1,4,7
only if i put a resistor, if i remove it, and connect 7 to GND directly there is no issues but that's not safe
your idea to focus on 1 digit work thanks
i will go to sleep i saw numbers everywhere......

Sleep, good idea. Tomorrow, remember, the resistors go on the segment lines, not the digit lines.

narzan · April 30, 2015, 1:28pm

morning back again 8)
this is the last update forget about everything i said and all codes before this

and this is the last code

int digit1 = A1; //PWM Display pin 1
int digit2 = 4; //PWM Display pin 4
int digit3 = 5; //PWM Display pin 5
int digit4 = 7; //PWM Display pin 7

//Pin mapping
int segA = 2; //Display pin 2
int segB = 6; //Display pin 6
int segC = 9; //Display pin 9
int segD = 11; //Display pin 11
int segE = 12; //Display pin 12
int segF = 3; //Display pin 3
int segG = 8; //Display pin 8

void setup() {                
  pinMode(segA, OUTPUT);
  pinMode(segB, OUTPUT);
  pinMode(segC, OUTPUT);
  pinMode(segD, OUTPUT);
  pinMode(segE, OUTPUT);
  pinMode(segF, OUTPUT);
  pinMode(segG, OUTPUT);

  pinMode(digit1, OUTPUT);
  pinMode(digit2, OUTPUT);
  pinMode(digit3, OUTPUT);
  pinMode(digit4, OUTPUT);
  
  pinMode(13, OUTPUT);
}

void loop() {
  
  //long startTime = millis();

  displayNumber(millis()/1000);

  //while( (millis() - startTime) < 2000) {
  //displayNumber(1217);
  //}
  //delay(1000);  
}

//Given a number, we display 10:22
//After running through the 4 numbers, the display is left turned off

//Display brightness
//Each digit is on for a certain amount of microseconds
//Then it is off until we have reached a total of 20ms for the function call
//Let's assume each digit is on for 1000us
//Each digit is on for 1ms, there are 4 digits, so the display is off for 16ms.
//That's a ratio of 1ms to 16ms or 6.25% on time (PWM).
//Let's define a variable called brightness that varies from:
//5000 blindingly bright (15.7mA current draw per digit)
//2000 shockingly bright (11.4mA current draw per digit)
//1000 pretty bright (5.9mA)
//500 normal (3mA)
//200 dim but readable (1.4mA)
//50 dim but readable (0.56mA)
//5 dim but readable (0.31mA)
//1 dim but readable in dark (0.28mA)

void displayNumber(int toDisplay) {
#define DISPLAY_BRIGHTNESS  500

#define DIGIT_ON  HIGH
#define DIGIT_OFF  LOW

  long beginTime = millis();

  for(int digit = 4 ; digit > 0 ; digit--) {

    //Turn on a digit for a short amount of time
    switch(digit) {
    case 1:
      digitalWrite(digit1, DIGIT_ON);
      break;
    case 2:
      digitalWrite(digit2, DIGIT_ON);
      break;
    case 3:
      digitalWrite(digit3, DIGIT_ON);
      break;
    case 4:
      digitalWrite(digit4, DIGIT_ON);
      break;
    }

    //Turn on the right segments for this digit
    lightNumber(toDisplay % 10);
    toDisplay /= 10;

    delayMicroseconds(DISPLAY_BRIGHTNESS); 
    //Display digit for fraction of a second (1us to 5000us, 500 is pretty good)

    //Turn off all segments
    lightNumber(10); 

    //Turn off all digits
    digitalWrite(digit1, DIGIT_OFF);
    digitalWrite(digit2, DIGIT_OFF);
    digitalWrite(digit3, DIGIT_OFF);
    digitalWrite(digit4, DIGIT_OFF);
  }

  while( (millis() - beginTime) < 10) ; 
  //Wait for 20ms to pass before we paint the display again
}

//Given a number, turns on those segments
//If number == 10, then turn off number
void lightNumber(int numberToDisplay) {

#define SEGMENT_ON  LOW
#define SEGMENT_OFF HIGH

  switch (numberToDisplay){

  case 0:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_ON);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_OFF);
    break;

  case 1:
    digitalWrite(segA, SEGMENT_OFF);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_OFF);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_OFF);
    digitalWrite(segG, SEGMENT_OFF);
    break;

  case 2:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_OFF);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_ON);
    digitalWrite(segF, SEGMENT_OFF);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 3:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_OFF);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 4:
    digitalWrite(segA, SEGMENT_OFF);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_OFF);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 5:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_OFF);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 6:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_OFF);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_ON);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 7:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_OFF);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_OFF);
    digitalWrite(segG, SEGMENT_OFF);
    break;

  case 8:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_ON);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 9:
    digitalWrite(segA, SEGMENT_ON);
    digitalWrite(segB, SEGMENT_ON);
    digitalWrite(segC, SEGMENT_ON);
    digitalWrite(segD, SEGMENT_ON);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_ON);
    digitalWrite(segG, SEGMENT_ON);
    break;

  case 10:
    digitalWrite(segA, SEGMENT_OFF);
    digitalWrite(segB, SEGMENT_OFF);
    digitalWrite(segC, SEGMENT_OFF);
    digitalWrite(segD, SEGMENT_OFF);
    digitalWrite(segE, SEGMENT_OFF);
    digitalWrite(segF, SEGMENT_OFF);
    digitalWrite(segG, SEGMENT_OFF);
    break;
  }
}

NOTE leg12 not (-) forget that in the pic, Leg1,4,5,7 is (-)
weird charterers on LED display
from what i understand 1,4,5,7 these legs for the digits
the second number for the segments
so my code must be like this

int digit1 = A1; //PWM Display pin 1
int digit2 = 4; //PWM Display pin 4
int digit3 = 5; //PWM Display pin 5
int digit4 = 7; //PWM Display pin 7

//Pin mapping 
int segA = 2; //Display pin 2
int segB = 6; //Display pin 6
int segC = 9; //Display pin 9
int segD = 11; //Display pin 11
int segE = 12; //Display pin 12
int segF = 3; //Display pin 3
int segG = 8; //Display pin 8

then why there is weird character in the display ?!
that's more hard than connect arduino to routers and make them communicate

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4 digit 7 segment display help in code!

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