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If we write 50 IF LOOPS means program become large and complex.

1) there is no such thing as an "IF LOOPS"
2) what is 'large and complex' about 50 lines of code?

In another method what elements we have to store in ARRAY.
you can di like this (based on the 50 if) with 2 tables

IF value > threshold[index] THEN led[index] := on;

Erik

If we write 50 IF LOOPS means program become large and complex.

1) there is no such thing as an "IF LOOPS"
2) what is 'large and complex' about 50 lines of code?

In another method what elements we have to store in ARRAY.
you can di like this (based on the 50 if) with 2 tables

IF value > threshold[index] THEN led[index] := on;

Erik

#define NumLeds 12
Value Threshold[NumLeds] =
    {
    // for each LED, list the value at which
    // the LED should turn on
    };


currentValue = GetCurrentValue();

// go through all LEDs, lowest to highest,
// and turn on all those LEDs for which the
// current value is greater than its threshold
for (led = 0; led < NumLeds; ++led)
   {
   if (currentValue >= Threshold[led])
       {
       // current value is at least high enough
       // to activate this LED
       SetLed (led, LedOn);
       }
   else
       { // turn off LEDs
       // current value no longer high enough
       // to activate this LED
       SetLed (led, LedOff)
       }
   }

Thanks for reply

Here I wane glow 50 leds means I have to send 50 ones on to the port.

My doubt is how to store the 50 ones in the array?

Here I well use 7 latches (8 bit data * 7 latches =48 bits).

So I well send only 8 bits on to the port. For 48 bits I want send 7 times on to the PORT.

Ex:


/* First 8 bits */

C1=0;/* latch disable*/
P1=8 bit data;
C1=1;/* latch enable*/


/*Second 8 bits */

C1=0;/* latch disable*/
P1=8 bit data;
C1=1;/* latch enable*/


/* Third 8 bits */

C1=0;/* latch disable*/
P1=8 bit data;
C1=1;/* latch enable*/

:
:


/* Seven 8 bits */

C1=0;/* latch disable*/
P1=8 bit data;
C1=1;/* latch enable*/


How to divide the 48-bit number in to seven 8-bit numbers?

Regards
Sri

"How to divide the 48-bit number in to seven 8-bit numbers?"

Why 48 bits?
If you have 50 LEDs, you need 50 bits!

Keil C51 doesn't have any data type larger than 32 bits anyhow, so you can't do it directly.

Easiest way is probably to have a 7-byte array:

array[0] holds bits 0-7;
array[1] holds bits 8-15;
:
:
array[6] holds bits 48-55 (note you have some spare bits here).

Hint: Look up the Modulus operator, '%' (percentage sign), in your 'C' textbook - it will come in useful in deciding which bit to set in which byte of the array...