adafruit/Adafruit-Raspberry-Pi-Python-Code — pull request #97 by charkes (2014-11-13 12:38:59+00:00)
Title: Suggested fix for direction caching problem in MCP230xx

If, after setting pin direction on bank B, you set a pin direction on bank A, the direction cache is overwritten with only bank A data. Suggested fix separates direction variables for banks A and B, overwrites as needed, and integrates the two banks back into direction cache.