Construct UART Data Frame with Parity Bit

Code

#include <stdio.h>
#include <stdint.h>

typedef struct {
    uint8_t parity_enable : 1;
    uint8_t parity_type   : 1;
    uint8_t reserved      : 6;
} UART_Control;

uint8_t create_uart_frame(uint8_t data, UART_Control *ctrl) 
{
    uint8_t temp=data;
    temp=temp&0x7F; 
    
    
    if(ctrl->parity_enable)
    {
        int count=0; //logic for number of set bits in 7bit data.
        while(data) //This is more optimized way to count number of set bits.
        {
          count++;
          data=data&(data-1);
        }
        
        if(ctrl->parity_type==0) //If it is even parity
        {
            if(count%2==0) //and if count of setbits are even, then no changes in MSB.
               return temp; 
            else
               return (1<<7)|temp; // and if count of setbits are odd, then mark MSB as high
        }

        //if it is odd parity
        if(count%2==0) //in odd parity, if number of 1's are odd, then mark it zero.
          return  (1<<7)|temp;
        
        return temp;
        
    }



    return temp;
}

int main() {
    uint8_t data;
    scanf("%hhu", &data);  // 7-bit input

    uint8_t parity_enable, parity_type;
    scanf("%hhu %hhu", &parity_enable, &parity_type);

    UART_Control ctrl;
    ctrl.parity_enable = parity_enable;
    ctrl.parity_type = parity_type;

    uint8_t frame = create_uart_frame(data, &ctrl);
    printf("frame = 0x%02X", frame);

    return 0;
}

Solving Approach