Function Module

Function or major requirements for the module I / O can be divided into several categories as follows:

     Control and timing
     CPU communication
     communication device
     data Buffering
     error detection

If the system uses the bus system, so any interaction between the CPU with I / O module will involve one or more bus arbitration. Module I / O should have the ability to carry out communication with the CPU and external devices. CPU communication include:

     Command Decording: I / O module receives commands from the CPU.
     Data: Data is exchanged between the CPU with I / O module via the data bus.
     Status reporting: Due to very slow peripheral, then the status of the module I / O needs to be known.
     Address recognition: As word of memory has an address, as well as premises perngkat I / O.

I / O module must be able to form a communication device (communication device). This communication includes commands, status information, and data. The main task of the data I / O is data buffering. Module I / O is often responsible for error detection and reporting.