76. Construct UART Data Frame with Parity Bit

#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
    if ( !(ctrl -> parity_enable) ) {
        data &= ~(1 << 7); //Make sure 7th bit is 0
        return data;
    }

    int totOnes = 0;
    uint8_t temp = data;

    while(temp > 0) {
        totOnes += temp & 0x01;
        temp >>= 1;
    }

    if ( !(ctrl -> parity_type) ) { 
        if (totOnes & 0x01) {
            data |= (1 << 7);
        } else {
            data &= ~(1 << 7);
        }
    } else {
        if (totOnes & 0x01) {
            data &= ~(1 << 7);
        } else {
            data |= (1 << 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;
}