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0740-7475/00/$10.00 © 2000 IEEE July-September 2000
IEEE STD 1394,
1
referred to as FireWire, is
one of the most widely accepted solutions to the
growing need for mass information transfer
among computers, storage devices, printers, dig-
ital video/audio devices, and so on. It consists of
a hardware and software standard for transport-
ing digital data at up to 400 megabits per second
today and 800 Mbps or more in the future. IEEE
1394 provides two types of data transfer: asyn-
chronous and isochronous. Asynchronous data
transmission, the traditional method for trans-
mitting data between computers and peripher-
als, is used for nodes not requiring a precise
timing reference. Isochronous data transfer pro-
vides data transport at a predetermined rate
1
and
is especially important for real-time digital mul-
timedia applications in consumer electronics.
We designed a 1394 physical layer (phy-
layer) and physical-link interface (PHY-LINK)
integrated-circuit core, targeting a transmission
rate of 400 Mbps and more. Design develop-
ment began with a behavioral VHDL descrip-
tion based on the 1394 specifications. We used
the VHDL model to simulate the protocol fea-
tures and performance. This phase required a
large debugging effort to correct inconsistencies
in the standard documentation. We subscribed
to the official 1394 Trade Association mailing list
(www.STDS-1394@IEEE.org) and participated
in discussions concerning possible modifica-
tions to the standard documentation. As a result,
we obtained a product compliant with the IEEE
1394a standard specification.
2
The second part of the project entailed devel-
oping a structural VHDL description of the core
and synthesizing it to the gate level by means of
a standard logic synthesizer (Synopsys, version
3.5a). The design is intended as a reusable intel-
lectual property (IP) that can be mapped to any
customer’s technology and included in a larger
custom design. Targeting the phy-layer and
PHY-LINK allowed our design to have the broad-
est range of reusability, because it does not
include application-dependent features. To
establish a performance evaluation, we mapped
the gate-level netlist on industrial, fully static,
0.35-micron CMOS standard-cell technology
(Corelib HCMOS6 from ST Microelectronics).
Finally, we tested the project through gate-level
simulations based on the extracted postlayout
parasitics in standard delay format (SDF).
This article describes the architecture and
the hardware design solutions we used to satis-
fy the IEEE 1394a specifications.
2
Several 1394
Trade Association
3
members have devised
other interesting commercial products:
Semicustom Design of an
IEEE 1394-Compliant
Reusable IC Core
In 0.35-micron standard-cell CMOS technology,
this IC core design supports a data rate of up to
400 Mbps and includes circuit blocks that operate
at a clock frequency of 400 MHz.
Mauro Bertacchi
ST Microelectronics
Alessandro De Gloria
University of Genoa
Daniele Grosso
Cadence Design Systems
Mauro Olivieri
University of Rome “La Sapienza”