45. 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];

    // Your logic to fill buffer
    // Then print buffer
    buffer[0] = 0xA5;
    buffer[1] = command;
    buffer[2] = (uint8_t) (value & ((1 << 8) - 1));
    buffer[3] = (uint8_t) ((value >> 8) & ((1 << 8) - 1));
    buffer[4] = status;
    for(int i = 0; i < 4; i++) {
        buffer[5 + i] = (uint8_t) ((checksum >> (8 * i)) & ((1 << 8) - 1));
    }
    buffer[9] = 0x5A;

    for(int i = 0; i < 10; i++) printf("%hhu ", 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;
}