This APM32F103CBT6 is somewhat interesting STM32F103 clone that has 128KB of flash and can run at 96MHz with usb working (real STM32F103 can only do 72MHz). It even has interesting memory mapped single precision FPU that seems to work. So I made Espruino build that run on that chip at 96MHz.
These dongles are cheap, small and versatile but the ram/flash is pretty small (20KB,128KB) so the Espruino build is stripped down but still it can be used for small USB to GPIO/SPI/I2C projects. The usb stick like form factor with metal case and pin header on the other side can be handy.
And btw this one is also nice because it has two LEDs, no strong pull resistors on B6/B7 and even have extra A9/A10 and BOOT0 pads available on PCB so apart from SWD can be flashed via serial bootloader and those two more GPIOs are also readily available for extra HW uart.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Just a small followup - I found aliexpress store that sells those STLink V2 dongles (board photo https://ibb.co/m4MpRhB) with Geehy APM32F103CBT6 https://www.geehy.com/apm32?id=14
This APM32F103CBT6 is somewhat interesting STM32F103 clone that has 128KB of flash and can run at 96MHz with usb working (real STM32F103 can only do 72MHz). It even has interesting memory mapped single precision FPU that seems to work. So I made Espruino build that run on that chip at 96MHz.
These dongles are cheap, small and versatile but the ram/flash is pretty small (20KB,128KB) so the Espruino build is stripped down but still it can be used for small USB to GPIO/SPI/I2C projects. The usb stick like form factor with metal case and pin header on the other side can be handy.
The shop is here https://www.aliexpress.com/item/1005001621626894.html but no guarantee you'll get same chip too. I got it twice and made third order. Anyway, it is no big deal, just small heads up.
And btw this one is also nice because it has two LEDs, no strong pull resistors on B6/B7 and even have extra A9/A10 and BOOT0 pads available on PCB so apart from SWD can be flashed via serial bootloader and those two more GPIOs are also readily available for extra HW uart.