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];
     buffer[0] = 0xA5 ; 
     buffer[1] = command ; 
     buffer[3] =  value >>8 ; 
     value<<=8 ; 
     buffer[2]  = value>>8  ; 
     buffer[4] =status ; 
     buffer[8] = checksum >>24;
     int reg1 = checksum>> 16 ; 
     checksum <<= 16 ; 
     int reg2 = checksum>>16; 
     buffer [6] =reg2>> 8; 
     reg2<<=8 ; 
     buffer [5] =reg2 >>8 ; 
     reg1<<=8 ; 
     buffer [7] =reg1>>8 ; 
     buffer [9] =0x5A ; 
     for(int i =0 ; i<10 ; i++){
        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;
}