Controllers
Peripherals must each have a chip designated as the ‘controller’ to communicate with the CPU.
The EDB connects each of these controllers to the CPU.
List of Controllers
Chipsets
Motherboards with independent controllers used to have a lot of chips scattered all over the place.
Motherboard manufacturers started to bundle multiple controllers into chipsets which are a smaller set of chips.
These days, almost all controllers are packed into one chipset.