79. Extract Packet Fields from Byte Stream

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

typedef struct {
    uint8_t start;
    uint8_t command;
    uint16_t data;
    uint8_t crc;
    uint8_t end;
} Packet;

typedef union
{
   Packet pkt;
   uint8_t buffer[6];
}frame;
/*
void print_packet_fields(uint8_t *buffer) {
    // Overlay struct and print values
    frame uart_frame;
    for(int i = 0; i < 6; i++)
    {
        uart_frame.buffer[i] = buffer[i];
    }
 
    printf("Start: %d\n", uart_frame.pkt.start);
    printf("Command: %d\n", uart_frame.pkt.command);
    printf("Data: %d\n", uart_frame.pkt.data);
    printf("CRC: %d\n", uart_frame.pkt.crc);
    printf("End: %d", uart_frame.pkt.end);
}
*/

void print_packet_fields(uint8_t *buffer) {
    // Overlay struct and print values
    Packet *pkt = (Packet*)buffer;
 
    printf("Start: %u\n", pkt->start);
    printf("Command: %u\n", pkt->command);
    printf("Data: %u\n", pkt->data);
    printf("CRC: %u\n", pkt->crc);
    printf("End: %d", pkt->end);
}


int main() {
    uint8_t buffer[6];
    for (int i = 0; i < 6; i++) {
        scanf("%hhu", &buffer[i]);
    }
    print_packet_fields(buffer);
    return 0;
}