Large Digit Driver (Turn off all Segments)

Development Boards Arduino
1

I’m not really sure how the code for the Large Digit Driver’s works for this. By Default the display segments are illuminated. I want to turn off all the segments on the large 7 segment displays (2 of them joined) (thus looking like the display is off). How would I do that in the code?

I am using the guide below as a reference. I am using the functions postNumber and showNumber word for word so far. I don’t completely get the shift registries yet.

https://learn.sparkfun.com/tutorials/la … okup-guide

Thanks for any help you guys can offer.

2

I figued it out. I essentially wanted any zero’s showing up in a number that way below 10 to just be blank (Example: 00, 01, 02. 03, - 09) but those 10 thru 99 to show the zero. I just modified the code slightly for postNumber and got what I wanted.

Old Code:

//Given a number, or '-', shifts it out to the display
void postNumber(byte number, boolean decimal)
{
  //    -  A
  //   / / F/B
  //    -  G
  //   / / E/C
  //    -. D/DP

#define a  1<<0
#define b  1<<6
#define c  1<<5
#define d  1<<4
#define e  1<<3
#define f  1<<1
#define g  1<<2
#define dp 1<<7

  byte segments;

  switch (number)
  {
    case 1: segments = b | c; break;
    case 2: segments = a | b | d | e | g; break;
    case 3: segments = a | b | c | d | g; break;
    case 4: segments = f | g | b | c; break;
    case 5: segments = a | f | g | c | d; break;
    case 6: segments = a | f | g | e | c | d; break;
    case 7: segments = a | b | c; break;
    case 8: segments = a | b | c | d | e | f | g; break;
    case 9: segments = a | b | c | d | f | g; break;
    case 0: segments = a | b | c | d | e | f; break;
    case ' ': segments = 0; break;
    case 'c': segments = g | e | d; break;
    case '-': segments = g; break;
  }

  if (decimal) segments |= dp;

  //Clock these bits out to the drivers
  for (byte x = 0 ; x < 8 ; x++)
  {
    digitalWrite(segmentClock, LOW);
    digitalWrite(segmentData, segments & 1 << (7 - x));
    digitalWrite(segmentClock, HIGH); //Data transfers to the register on the rising edge of SRCK
  }
}

New Code:

//Given a number, or '-', shifts it out to the display
void postNumber(byte number, boolean decimal)
{
  //    -  A
  //   / / F/B
  //    -  G
  //   / / E/C
  //    -. D/DP

#define a  1<<0
#define b  1<<6
#define c  1<<5
#define d  1<<4
#define e  1<<3
#define f  1<<1
#define g  1<<2
#define dp 1<<7

  byte segments;

  switch (number)
  {
    case 1: segments = b | c; break;
    case 2: segments = a | b | d | e | g; break;
    case 3: segments = a | b | c | d | g; break;
    case 4: segments = f | g | b | c; break;
    case 5: segments = a | f | g | c | d; break;
    case 6: segments = a | f | g | e | c | d; break;
    case 7: segments = a | b | c; break;
    case 8: segments = a | b | c | d | e | f | g; break;
    case 9: segments = a | b | c | d | f | g; break;
    case 0: 
      if (numentry > 9) {
        segments = a | b | c | d | e | f; break;
      } else segments = 0; break;
      
    case ' ': segments = 0; break;
    case 'c': segments = g | e | d; break;
    case '-': segments = g; break;
  }

The only change I made was the case 0 and added an if statement doing what I wanted. I couldn’t figure out how to invoke the ’ ’ case switch from within showNumber since it needs an integer. But this worked out great. Hope it helps somebody else one day!

3

This is probably a simple question, but when I add this to the original code, I get ‘numentry’ was not declared in this space. What do I have to do to make this work?

Thanks.

Murphy