build_frame

a

Function build_frame 

Source 
pub fn build_frame(payload: &str) -> String
Expand description

Wrap a payload into a standard HJ212 frame (HJ 212—2025 6.3.2): ## + 4-digit length + payload + 4-hex CRC + \r\n.

Notes:

  • Length is the ASCII byte length of payload
  • CRC is HJ 212—2025 “ANSI CRC16” over the payload, rendered as uppercase hex