Hc-12 Firmware Here

Carefully pry open the plastic case or use the bare PCB version. Locate the main microcontroller. Most modern HC-12s use an (20-pin TSSOP). Look for the SWIM (single wire interface module) pin – usually pin 4 (PA0/SWIM).

Because the HC-12 uses a standard STM8S003F3P6 microcontroller, it is possible to bypass the manufacturer's firmware and upload custom code. GitHubhttps://github.com hc-12 firmware

Note: The module must be connected to a PC or MCU via a USB-to-TTL converter at to accept commands, regardless of what baud rate you set for data mode. Essential HC-12 AT Commands AT : Test command, returns OK . Carefully pry open the plastic case or use