Serialized Data Buffer

Code

#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];

    buffer[0] = (uint8_t)0xA5u;
    buffer[1] = command;
    buffer[2] = (uint8_t)(0x00FF & value);
    buffer[3] = (uint8_t)((0xFF00 & value) >> 8);
    buffer[4] = status;
    for(int i = 5; i < 9; i++){
        buffer[i] = (uint8_t)(0x000000FF & (checksum >> ((i - 5) * 8)));
    }
    buffer[9] = (uint8_t)0x5Au;

    for(int j = 0; j < 10; j++){
        printf("%u ", buffer[j]);
    }
}

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;
}

Solving Approach