Harold,

thanks for your replay.
Your brought interesting point on ADC conversion.
suppose I am looking for 951  I better test for 949-953

if ((adc_x>948)&&(adc_x<954))		// looking for 951

do you think above example will work?

thanks for your help

Andre




Harold Hallikainen wrote:

>Without all the elses, the if's after the successful test will continue to
>run. That is, every test will be run every time. With the elses, tests
>after the success will be skipped. Another way to do this, which is, I
>believe, more readable, is to use the switch-case statement.
>
>I am surprised that you are testing for 10 specific ADC values. It is
>unlikey that successive ADC readings will land on exactly a particular
>number. More likely they will be one count higher or lower, perhaps more
>variation depending on circuit stability. Do yo want to test the ADC for a
>range of values? If so, the if, or if else if test seem to be he only way
>to go (or a very large switch-case statement or a large array where the
>ADC indexes into it).
>
>Harold
>
>
>  
>
>>Hi to all engineers,
>>
>>I am reading ADC to compare 10 different values  if they are matched
>>then each match
>>has it's own set value. my question is.
>>
>>1. what is the different between  if else if  for example
>>
>>    if (adc_x==1023)        // 5v         1023
>>            {
>>            xbyte_lsb=0xff ;
>>            xbyte_msb=0x01 ;
>>            }
>>            else if (adc_x==921)   // 4,5v       921
>>            {
>>            xbyte_lsb=0x9A ;
>>            xbyte_msb=0x01 ;
>>            }
>>
>>or  without else if
>>
>>    if (adc_x==1023)        // 5v         1023
>>            {
>>            xbyte_lsb=0xff ;
>>            xbyte_msb=0x01 ;
>>            }
>>            if (adc_x==921)   // 4,5v       921
>>            {
>>            xbyte_lsb=0x9A ;
>>            xbyte_msb=0x01 ;
>>            }
>>
>>I do not clearly understand what does "else if"  do?
>>
>>is there better way of testing ADC ?
>>
>>Any feedback will appreciate.
>>
>>Andre
>>--
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>>    
>>
>
>
>  
>

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