pyusb wrappers for using a ch341 in i2c mode.
Somewhat based on [email protected]:commandtab/ch341eeprom.git but more openended, and not feeling the need to do everything in C.
usb2i2c: https://code.google.com/p/usb2i2c/ seems to be identical protocols, possibly earlier versions of the same chips. (And there's code available! whee!)
Interesting ideas on directly getting/setting the status of the pins via "CH341GetInput"/"CH341SetOutput" see if that method is in the usb2i2c code? http://common-codebase.googlecode.com/svn-history/r70/trunk/others/python_test/i2c/CH341.py
More links here: https://hackingbtbusinesshub.wordpress.com/category/ch341/
Lots more datasheets and links down a bit on this thread: http://www.kenotrontv.ru/forum/topic/199-usb-%D0%BF%D1%80%D0%BE%D0%B3%D1%80%D0%B0%D0%BC%D0%BC%D0%B0%D1%82%D0%BE%D1%80-%D0%B4%D0%BB%D1%8F-flash-%D0%B8-eeprom-usb-bus-convert-chip-ch341/