Input / Output
by Mohd Faizal Mohamed Nor
1. programmed i/o is a method of transferring data between the Cpu and the peripherals such as a network adapter or an ATA storage devices. Each data item transfer is initiated by an instruction in the program involving the Cpu for every transaction.
2. Introduction
2.1. -a device which is connected to an i/o modules of computer is called peripheral devices. -Each module interfaces to the system bus or central switch and controls one or more peripheral devices.
3. Type of External Device
3.1. Human Readable
3.1.1. Human Readable is used for communicating with computer user.
3.1.1.1. created so that human can understand
3.1.2. -printer & video display terminal
3.2. Machine Readable
3.2.1. Suitable for communicating with equipment.
3.2.1.1. communicating with equipment
3.2.2. Magnetic disk and tape systems, sensor and actuators (used in robotics application).
3.3. Communication
3.3.1. they may be human readable device & machines readable device
3.3.1.1. communicating with remote devices
3.3.2. Terminal & modem network interface card (NIC).