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[on:]

Looking to convert a 'long to bcd' to drive 5 led displays.
(HP5082 -7302)

Is there a function in a library somewhere to do this, or will it have to be done from scratch.

I know things have moved on since these were about, but would just like to use them....

TIA.

[Reply #1 on:]

I'm sure there's a more efficient way to code this.

Code:

void BCD (unsigned long b, char* o)
{
   for (int i=10; i; --i)
   {
      *o = b % 10;
      b /= 10;
      o++;
   }
}

[Reply #2 on:]

I'm sure there's a more efficient way to code this.

Code:

void BCD (unsigned long b, char* o)
{
   for (int i=10; i; --i)
   {
      *o = b % 10;
      b /= 10;
      o++;
   }
}

Shouldn't you be packing two digits per byte (one nibble per digit) if you're outputting BCD?

[Reply #3 on:]

I'm sure there's a more efficient way to code this.

Code:

void BCD (unsigned long b, char* o)
{
   for (int i=10; i; --i)
   {
      *o = b % 10;
      b /= 10;
      o++;
   }
}

Shouldn't you be packing two digits per byte (one nibble per digit) if you're outputting BCD?

You're probably right, but his wasn't clear what he wanted.

[Reply #4 on:]

And probably should use byte (which is unsigned) instead of char (which is signed).

[Reply #5 on:]

I thought about that but the stored values are small enough that it doesn't really matter.

[Reply #6 on:]

the basic BCD packaging:

Code:

uint8_t dec2bcd(uint8_tdec)
{
  return (dec/10)*16 + (dec%10);
}

uint8_t bcd2dec(uint8_t bcd)
{
  return (bcd/16) * 10 + bcd%16;
}

For longer numbers one need a BCD array

[Reply #7 on:]

Thanks for the info.
The 'data' to be displayed presently, is just a counter.
The solutions are somewhat more simple than i'd anticipated.

Which is great news!

I've found the displays are actually HP5082 -7340
- which means, I can display the number in Decimal or Hex
Of course in Hex, I won't need to use the conversion.