Modules in FG interface are Object Class , as like a map, to build a new object. You have learned about HT16K33 and MCP23017 classes, they are Modules, special Modules named in FG Interface world Devices. I made this difference to split and make the difference between switch , displays .. etc and the hardware driver chip.
All Modules Classes are loaded into the interface, ready to be used and can be requested with the getModule() Interface Method.

To be loaded, the module need to be declared. For memory, the main config file :

[INT]
intname=RADIOPANEL
deviceconf=/opt/fgint/Config/devices.cfg

[MODULES]
module01=FGIntHT16K33,HT16K33
module02=FGIntMCP23017,MCP23017
module03=FGIntSegDisplay,SegDisplay
module04=FGIntSwitch,Switch

[AUXCONF]
displays=/opt/fgint/Config/displays.cfg
switches=/opt/fgint/Config/switches.cfg

In the MODULES section, you can see all modules that will be loaded. Here We are loading HT16K33 from module file FGIntHT16K33.py. Same thing for the MCP23017 Module in the FGIntMCP23017.py and FGIntSegDisplay.py with the SegDisplay Class

Some Module file can handle more than one Class, as like FGIntSwitch.py where you can find different Class for different switch types. FGIntSwitch.py own the folling classes :

  • Switch : Single switch 2 states
  • DoubleSwitch : Single switch 3 states
  • RotarySwitch : Use to manage a rotary switch (variable nb position)
  • ToogleSwitch : Single Push button that will switch between 2 states at each push