Many of our Arduino compatible devices contain a CH340 USB to Serial IC instead of the much more expensive FTDI chip. The CH340 is common in Chinese product, but not as common in products designed in the rest of the world. What this ends up meaning is, it is sometimes problematic getting them working on your computer. To make things easier, the following drivers have been tested by us:
Windows Driver (2016-09-27)
Official Mac Driver (May have troubles 10.9 and later)
Signed Mac Driver (Should work with 10.9+)
Note that Windows 10 appears to include the driver, as does Linux. One extremely edge case, though, to be aware of: As of this writing, the Linux driver for the CH340 does not support parity. The STM32Duino we sell requires parity when installing the bootloader. To save yourself hours of hair-pulling, know that you will either need to use a different USB to Serial adaptor, or a different OS, or patch your kernel driver.