All kinds of satellite set-top box upgrades
The router, hard disk, ADSL, broadband, etc., can have their firmware updated or cracked.
Cell phones, XBOX360, GPS serial communication, auto-detection, DVD flash, etc.
And write STC SCM, NXP SCM, Renesas microcontroller, NEC microcontroller, etc.
Simple serial communication; the super terminal is a commonly used serial port debugging tool.
Electronics enthusiasts can use a USB signal to convert to a TTL signal.