STLINK V2.1

The ST Link V2/1 emulator is modified from the official ST development board schematic, adding USB TVS and TVS protection for the debug output port.
The MCU can be the Heze AIR32F103CBT6, which has been tested and confirmed to work correctly.
The firmware was collected online and can be freely upgraded using STM32CubeProgrammer. Each emulator has a different serial number and can be used simultaneously on a single PC.
Hardware compatibility: STLINK V2 supports STM8 debugging;
debugging STM8 requires mounting a 10k resistor (R16) and burning the V2 firmware. V2 also supports STM32 debugging.
V2/1 does not require mounting R16 and uses the V2.1 firmware; it cannot debug STM8, only STM32.
A reserved SWD programming contact is provided on the back, allowing other links to program additional firmware.
An ISP contact is also provided; if no other link is available, firmware can be programmed in ISP mode.
Shorting BT0 powers on to enter ISP mode, and firmware is programmed via ISP_TX and ISP-RX.
The USB is a 16-pin Type-C, supporting C2C cables. The debugging
interface is a standard HDR2.54 header, with a reserved MX1.25 4P debugging port on the back.
The outer shell is 3D printed from JLCPCB resin, and the model has a wall thickness of less than 0.8mm. Accept the printing risks during printing;
the panel is printed from JLCPCB panels, with a thickness of 1.0mm.