[PIC] Explanation for the below mentioned code which is mikro c program

[vinay.k]

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Code C - [expand]
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const unsigned char SinLkUpTab[50]={0,8,16,24,31,39,47,55,62,70,77,85,92,99,
106,113,120,127,134,144,147,153,159,165,171,177,182,188,193,198,202,207,
211,215,219,223,226,229,232,235,238,240,242,244,246,247,248,249,250,250};
unsigned short cnt,inc,dec,sqinc,cnt1;
void interrupt()
{
if(dec==0)
{cnt++;
PWM1_Set_Duty(SinLkUpTab[cnt]);
}
else if(dec==1)
{cnt--;
PWM1_Set_Duty(SinLkUpTab[cnt]);
}
TMR1IF_bit=0;
TMR1H=0xFF;
TMR1L=0x76;
}
void main()
{
TRISB=0;
PORTC=0;
PORTB=0;
TRISC=0;
TRISA=0;
PORTA=0;
T1CON=0b00000001;
TMR1IF_bit=0;
TMR1H=0xFF;
TMR1L=0x76;
TMR1IE_bit=1;
cnt=0;
sqinc=0;
cnt1=0;
inc=0;
dec=0;
PWM1_Init(20000);
PWM1_Start();
INTCON=0xC0;
PORTA.b0=1;
while(1){
if(cnt==49&&dec==0)
{
dec=1;
}
else if(cnt==0&&dec==1)
{
PORTB.B1=~PORTB.B1;
dec=0;
}
}
}

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[andre_luis]

The program is self explanatory: It is an up/down counter that scans a table of values of a sinusoid to be loaded into PWM module of microcontroler, and represents the duty-cycle for the output. The code probably is part of an inverter. Depending on circuit topology, output B1 can be used to select the pair of devices that will be switched at current half cycle of the waveform.