Serialized Data Buffer

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

void build_packet(uint8_t command, uint16_t value, uint8_t status, uint32_t checksum) {
    uint8_t buffer[10];
    uint8_t *pkt = buffer;
    // Your logic to fill buffer
    *pkt = 0xa5;
    ++pkt;
    *pkt = command;
    ++pkt;
    *pkt = (uint8_t)value;
    ++pkt;
    *pkt = value >> 8;
    ++pkt;
    *pkt = status;
    ++pkt;
    
    uint8_t *chk_sum = (uint8_t *)&checksum; 
    for (int i = 0; i < sizeof(checksum); ++i, ++pkt, ++chk_sum) {
        *pkt = *chk_sum;
    }
    *pkt = 0x5a;

    // Then print buffer

    for(int i = 0; i < sizeof(buffer); ++i) {
        if (i) {
            printf(" ");
        }
        printf("%d", buffer[i]);
    }
}

int main() {
    uint8_t cmd, status;
    uint16_t val;
    uint32_t crc;

    scanf("%hhu %hu %hhu %u", &cmd, &val, &status, &crc);
    build_packet(cmd, val, status, crc);
    return 0;
}