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;

int countSetBits(int n) {
    int count= 0;
    while(n) {
        n &= (n - 1);
        count++;
    }
    return count;
}

uint8_t create_uart_frame(uint8_t data, UART_Control *ctrl) {
    // Your logic here
    uint8_t frame = 0;

    if (ctrl->parity_enable == 0) {
        frame = data;
    }
    else {
        int count = countSetBits(data);
        frame = data;
        if (ctrl->parity_type == 1) {
           if (count % 2 == 0) {
            frame |= (1 << 7);
           }
        } 
        else {
            if (count % 2 != 0) {
            frame |= (1 << 7);
           }
        }

    }
    return frame;
}

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