[PIC] How define the lower and upper char(s) of an integer?

[Samitha_ediriweera]

How to define the lower and upper char(s) of an integer?

hi guys,

this is the code(s), i currently know,

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Code C - [expand]
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union v{
    unsigned int vint;
    unsigned char vchar[2];
};
 
main()
{
    union v data;
 
    data.vchar[0]=ADRESL;
    data.vchar[1]=ADRESH;
    adc=data.vint;
}

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Also,

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Code C - [expand]
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main()
{
    adc = (ADRESL | (ADRESH<<8));
}

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isn't there a way i could define the adc lower & upper char(s) so that,

when ADRESL=0x34; and ADRESH=0x12; , then, adc reads 0x1234.

i.e. get the compiler to read ADRESL as the lower char & ADRESH as upper char of adc.

thanks in advance.

SAM

 

[andre_luis]

You are probably working with an 8-bit CPU core, which due to its internal data bus is limited to this magnitude, all access to internal registers must be done byte per byte.

 

[milan.rajik]

Re: How to define the lower and upper char(s) of an integer?

It is not clear what exactly you want.

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Code C - [expand]
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unsigned int adcResult = 0; //10 bit adc result fits in 16 bit type
unsigned char lowByte  = 0, highByte = 0; //holds adcResult split into bytes
 
 
 
void main() {
 
 
    while(1) {
    
            
        lowByte = ADRESL;   //ADC result right justified
        highByte = ADRESH;
 
        adcResult = (highByte << 8) | lowByte;
 
        //or
 
        adcResult = (ADRESH << 8) | ADRESL;
     
 
    }   
}

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[Samitha_ediriweera]

yes. it's a pic16f877a

 

[milan.rajik]

See if this works

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Code C - [expand]
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#define ADC_RESULT {(ADRESH << 8) | ADRESL}
 
 
unsigned int adcResult = 0;
 
adcResult = ADC_RSEULT;

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