MDIA 308MDIA 308

ComputersComputers

Computers

• Most PCs are based on a standard architecture

• The computer is constructed of various subunits

Computer architecture

Computers

• Subunits of the computer are attached to the printed circuit board called the “motherboard”

• The CPU is the computer’s “brain” and executes the calculations required to perform the various functions

• Other subunits are attached to the motherboard as “daughterboards”

Central Processor

Daughtercards

Computer memory

• Short term storage call “random access memory (RAM) retains data only while the computer is operating

• Long term data storage is accomplished using internal hard drives, or external storage devices such as solid state drives (compact flash, secure digital, etc.)

RAM

Hard drives

• Hard drives use the same magnetic recording principles used in tape

• Hard drives are constructed by fixing oxide to a polished glass or aluminum platter

• Hard drives contain multiple platters attached to a common spindle

• The tiny recording and playback heads move across the disk surface without touching it

Hard drives

Hard drives

Optical storage

• Compact disks (CD) and digital versatile disks (DVD) offer permanent external storage

• Optical storage has the advantage of being less volatile than magnetic storage

• Optical storage can be very high capacity

Connecting peripherals

• Peripheral or outboard devices may be connected to the computer

• Various protocols exist to connect peripherals– Parallel and Serial Buses– Universal Serial Bus (USB)– IEEE-1394 (FireWire)– Small Computer System Interface (SCSI)– Sony/Philips Digital Interface (S/PDIF)

Connecting peripherals

• Parallel and serial are older systems (legacy) that do not offer high enough throughput for most audio and video devices

• USB 2.0 provides fast data transfer• IEEE 1394 offers high data transfer

capacity and is “hot swapable”• SCSI and S/PDIF are less common and

used only for audio devices

Peripherals and interfaces

• Some peripherals are designed to allow audio and video inputs and outputs to be easily connected to the computer using standard audio connectors

• Other interface devices allow the user to have the same “tactile” experience as using a mixing console

USB audio interface

User interface

User interface

User interface

Software

• BIOS – basic input-output system– Permanent instructions on a chip– Called “firmware”– Instructions for organizing data flow

• Drivers – small software scripts that allow the computer to communicate with various hardware

Software

• Operating systems (OS) provide a consistent software platform for application software

• Most OS are single-user multitasking

• OS present a simple (text or graphic) system for the user to operate the software and hardware