CRC32 calculation example for serial frame

Payload string (before framing):

command=/check_status&data=eyJkb2N1bWVudEV4dElEIjoiT1JERVItMTAwMSJ9&sign=ZWIyMmVmNWNhY2Q3ZWViZjJmMzc2ZjZlYWQzMWI4ZGM5NDllM2M4Mg==

CRC input rules:

• Encode payload as UTF-8 bytes.
• Compute CRC32 over payload bytes.
• Replace CRC bytes 0x03 with 0x20 before writing CRC to frame.

Computed CRC:

• crc32_hex = 61387ab8
• CRC32_BE bytes = 61 38 7a b8

Final frame layout:

02 <payload_utf8_bytes> 61 38 7a b8 03

Where:

• 02 is STX
• 03 is ETX