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) {
    // Your logic here
     data &= ~(1 << 7);

    if (ctrl->parity_enable) {
        // Count set bits in lower 7 bits
        uint8_t temp = data;
        int count = 0;
        while (temp) {
            temp &= (temp - 1);
            count++;
        }

        // Determine parity bit
        int parity_bit;
        if (ctrl->parity_type == 0) {  // Even parity
            parity_bit = (count % 2 != 0);  // Set if count is odd
        } else {  // Odd parity
            parity_bit = (count % 2 == 0);  // Set if count is even
        }

        // Set parity bit at MSB (bit 7)
        data |= (parity_bit << 7);
    }

    return data;

}

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