Questions-1 Write a short note on Device Controller. OR Explain Device Controller in brief.
- I/O unit consist of a mechanical component and an electronic component. Electronic component of I/O devices is called the Device Controller.
- The mechanical component is device itself.
- The controller card usually has a connector on it, into which a cable leading to the device itself can be plugged.
- Some devices have their own built in controller. Many controllers have two, four or even eight identical devices.
- If the interface between the controller and device is a standard interfacing (ISO, ANSI or IEEE), then companies can make device or controller that fit that interface.
- The controllers are used to convert the serial bit stream into a block of bytes and perform any error correction if necessary.
- The block of bytes is typically first assembled bit by bit in buffer inside controller.
- After verification, the block has been declared to be error free, and then it can be copied to main memory.