Technical Explanations; About Ieee 1394 - Yamaha mLAN Manual Book

Technical Explanations

1. About IEEE 1394

This is a standard defined by the IEEE (Institute of Electrical and Electronics Engineers). It is being
use to implement low-cost high-speed digital networks that connect computer equipment to con-
sumer devices (audio equipment, video equipment, electronic musical instruments) or to connect
consumer devices to each other.
Although "IEEE 1394-1995" provides for a maximum of 400 Mbps (megabits per second) data
transfer between computer devices, the standard is being expanded to allow data transfer at
speeds of 1.6 Gbps (gigabits per second) in the future. At a speed of 200 Mbps, it is theoretically
possible to handle more than one hundred channels of CD-quality digital audio data simulta-
neously with musical data equivalent to more than 256 MIDI cables.
In addition, the numerous types of cables required by a conventional system to carry different
types of data such as video, audio, and MIDI are no longer needed, since all data is carried over a
single type of cable connected sequentially.
In the case of audio devices, conventional systems were connected in a radiating topology where
connections radiated from the AV amp to the various components (CD, MD, tuner etc.). In con-
trast, IEEE 1394 allows a simpler method of connection in which a single type of cable is used to
sequentially connect each device (amp CD MD tuner). No particular knowledge is required
when making connections, and new devices can be added to the system simply by connecting
them sequentially.
This also applies to networks connected to multimedia computers, AV devices, and electronic musi-
cal instruments, making it extremely simple to create more powerful systems than ever before.
Figure 2: Example of audio connections
Conventional connections: Attention must be paid to L/R and IN/OUT, and a limited number of devices
can be connected.
IEEE 1394 connections: No particular knowledge is required, and connections may be made in any
order. Up to 63 devices can be connected.
Technical points regarding IEEE 1394 are explained below.
10
AMP
CD
L
R
CD
AMP CD
IEEE 1394 compatible cable
MD MD TUNER
IN OUT
MD TUNER
MD TUNER