All Macs In-Depth Tests
Firewire Compared To The Current SCSI Standards

Firewire Connectors by Molex

Adaptec's AHA-8945 host adapter links both high-performance SCSI peripherals and 1394-enabled consumer electronics products to PCs and Macs using only one PCI slot.

Adaptec's implementation of the IEEE 1394 serial bus technology-the AHA-8940 host adapter-enabes PC and Macintosh computers to connect to current and emerging 1394 peripherals, including DV camcorders, digital VCRs, color printers, scanners, digital still cameras, DVD players, and more.


Firewire Links
USB Links


What is Firewire (IEEE 1394)?

FireWire is a cross-platform implementation of the high-speed serial data bus -- defined by IEEE Standard 1394 that can move large amounts of data between computers and peripheral devices.

IEEE 1394 was conceived by Apple Computer and then developed within the IEEE 1394 Working Group. The IEEE 1394 standard is a scalable, flexible, easy to use, low-cost digital interface that will integrate the worlds of consumer electronics and personal computers.

The market has been calling for one interface to connect all of it's components. The interface that can meet these needs is the IEEE standard 1394, called Firewire by its pioneers at Apple. 1394 is compatible with a wide range of devices as well as having speed and price advantages over current data transfer systems. The disadvantages of SCSI based systems are two fold. First SCSI is a parallel interface and second it is an expensive route for computer speed. The SCSI, as well as other parallel buses, have a very limited connectability. Firewire can connect almost all computer peripherals such as printers, scanners, modems, keyboards, displays (monitors), hard drives and CD-ROM drives.

Along with these computer peripherals Firewire will support the connection of digital cameras, digital camcorders and televisions, along with all other digital consumer audio and video equipment.

There has always been a compatibility gap between the use of these consumer electronics and computers. Typically a special feature card would be required to translate signals into something that the computer could understand, but now the world can just plug the universal connection (1394) into both the personal computer and consumer electronics.

Why another Bus?

Today when you "surf the web" for information and click on a "hot link" you must wait for the bit-mapped date to download. Imagine, selecting an icon and almost immediately that image is on your screen. FireWire is one of the technologies that will help make this future a reality.

Several key trends and requirements are emerging for the transfer of digital information:

  • Consumer electronics and computers are converging.
  • There is a desire to keep data digital for as long as possible as a means to reduce system cost, complexity, and improve signal integrity.
  • With the emergence of multimedia market, more and more data is video and audio.
  • The ability to work with time sensitive data is growing in importance.
  • Miniaturization is continuing. Small products are favored for portability, convenience, and material usage resources.
  • Consumers are beginning to purchase computers the way they choose consumer electronics.Their criteria are: reliability, convenience, and simplicity.
  • The need and desire for Peer to Peer computing is growing.
  • The master-slave model is changing as computing becomes distributed.


FireWire Advantages

FireWire provides many advantages over other peripheral interconnection technologies. The cables are as simple to connect as a telephone cord--there is no need for screws or latches. And, unlike SCSI technology, FireWire is autoconfiguring--so it eliminates SCSI device ID conflicts and the need for terminators. FireWire is also a hot plug-and-play technology, which means that a device can be disconnected and then reconnected without the need to restart the computer. FireWire is fast--it can transfer digital data at 200 megabits per second, with a planned increase to 400 megabits per second and beyond. And, the FireWire technology supports expansion--up to 63 devices can be attached on the same FireWire bus. Finally, FireWire includes support for isochronous data transfer, which provides guaranteed bandwidth for real-time video and audio streams.

  • Real-time data transfer for multimedia applications 100, 200, & 400Mbits/s data rates today; 800 Mbits/s and multi-Gbits/s upgrade path
  • Live connection/disconnection without data loss or interruption
  • Automatic configuration supporting "plug and play"
  • Free form network tool allowing mixing branches and daisy-chains
  • No separate line terminators required
  • Guaranteed bandwidth assignments for real-time applications
  • Common connectors for different devices and applications
  • One of the most important uses of FireWire as the digital interface for consumer electronics and AV peripherals. FireWire is a peer-to-peer interface. This allows dubbing from one camcorder to another without a computer. It also allows multiple computers to share a given peripheral without any special support in the peripheral or the computers.

    System Requirements

    FireWire PCI-card solutions are compatible with any Power Macintosh or Mac OS-compatible computer with an available PCI slot and Mac OS Version 7.6 or higher.

    Theoretical Transfer Speed Rates Of Various Ports Compared


    Theoretical Maximum Throughput

    Theoretical Maximum Throughput

    Used For

    Apple Desktop Bus

    0.01 Mbps or 10 Kbps


    input devices like mice, keyboards, joysticks, etc

    Serial Port

    0.23 Mbps or 230 Kbps


    printers, telephony devices, modems, etc

    USB at low data transfer rate

    1.5 Mbps


    most devices

    Geoport Port

    2 Mbps


    Geoport modem


    10 Mbps


    Laser printers, network connections, etc

    USB at high transfer rates

    12 Mbps


    most devices


    40 Mbps


    hardrives, removable storage, scanners, etc

    Fast SCSI

    80 Mbps


    high performance drives


    100 Mbps


    Laser printers, network connections, etc

    Ultra SCSI

    160 Mbps


    high performance drives

    Wide Ultra SCSI

    320 Mbps


    high performance drives

    Ultra2 SCSI

    320 Mbps


    high performance drives


    400 Mbps


    hard drives, scanners, digital video

    USB 2.0 (Intel)

    480 Mbps


    Standard due in late 2000 or early 2001

    Wide Ultra2 SCSI

    640 Mbps


    high performance drives


    800 Mbps


    hard drives, scanners, digital video
    Now available (3/21/00)

    Ultra3 SCSI

    1280 Mbps


    high performance drives


    1600 Mbps


    hard drives, scanners, digital video
    (Design spec up and running 3/21/00)