© 2005 Ubicom, Inc. All rights reserved.
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www.ubicom.com
SX20AC/SX28AC
1.3 Architecture
The SX devices use a modified Harvard architecture.
This architecture uses two separate memories with sepa-
rate address buses, one for the program and one for
data, while allowing transfer of data from program mem-
ory to SRAM. This ability allows accessing data tables
from program memory. The advantage of this architec-
ture is that instruction fetch and memory transfers can be
overlapped with a multi-stage pipeline, which means the
next instruction can be fetched from program memory
while the current instruction is being executed using data
from the data memory.
Ubicom has developed a revolutionary RISC-based
architecture and memory design techniques that is 20
times faster than conventional MCUs, deterministic, jitter
free, and totally reprogramable.
The SX family implements a four-stage pipeline (fetch,
decode, execute, and write back), which results in execu-
tion of one instruction per clock cycle. For example, at
the maximum operating frequency of 75 MHz, instruc-
tions are executed at the rate of one per 13.3ns clock
cycle.
1.3.1 The Virtual Peripheral Concept
Virtual Peripheral concept enables the "software system
on a chip" approach. Virtual Peripheral, a software mod-
ule that replaces a traditional hardware peripheral, takes
advantage of the Ubicom architecture's high performance
and deterministic nature to produce same results as the
hardware peripheral with much greater flexibility.
The speed and flexibility of the Ubicom architecture com-
plemented with the availability of the Virtual Peripheral
library, simultaneously address a wide range of engineer-
ing and product development concerns. They decrease
the product development cycle dramatically, shortening
time to production to as little as a few days.
Ubicom's time-saving Virtual Peripheral library gives the
system designers a choice of ready-made solutions, or a
head start on developing their own peripherals. So, with
Virtual Peripheral modules handling established func-
tions, design engineers can concentrate on adding value
to other areas of the application.
The concept of Virtual Peripheral combined with in-sys-
tem re-programmability provides a power development
platform ideal for the communications industry because
of the numerous and rapidly evolving standards and pro-
tocols.
Overall, the concept of Virtual Peripheral provides bene-
fits such as using a more simple device, reduced compo-
nent count, fast time to market, increased flexibility in
design, customization to your application, and ultimately
overall system cost reduction.
Some examples of Virtual Peripheral modules are:
· Communication interfaces such as I
2
CTM, MicrowireTM
(µ-Wire), SPI, IrDA Stack, UART, and Modem func-
tions
· Frequency generation and measurement
· PPM/PWM output
· Delta/Sigma ADC
· DTMF generation/detection
· PSK/FSK generation/detection
· FFT/DFT based algorithms
1.3.2 The Communications Controller
The combination of the Ubicom hardware architecture
and the Virtual Peripheral concept create a powerful, cre-
ative platform for the communications design communi-
ties: SX communications controller. Its high processing
power, recofigurability, cost-effectiveness, and overall
design freedom give the designer the power to build
products for the future with the confidence of knowing
that they can keep up with innovation in standards and
other areas.
1.4 Programming and Debugging Support
The SX devices are currently supported by third party
tool vendors. On-chip in-system debug capabilities have
been added, allowing tools to provide an integrated
development environment including editor, macro assem-
bler, debugger, and programmer. Un-obtrusive in-system
programming is provided through the OSC pins. There is
no need for a bon-out chip, so the user does not have to
worry about the potential variations in electrical charac-
teristics of a bond-out chip and the actual chip used in the
target applications. the user can test and revise the fully
debugged code in the actual SX, in the actual application,
and get to production much faster.
1.5 Applications
Emerging applications and advances in existing ones
require higher performance while maintaining low cost
and fast time-to-production.
The device provides solutions for many familiar applica-
tions such as process controllers, electronic appli-
ances/tools, security/monitoring systems, consumer
automotive, sound generation, motor control, and per-
sonal communication devices. In addition, the device is
suitable for applications that require DSP-like capabili-
ties, such as closed-loop servo control (digital filters), dig-
ital answering machines, voice notation, interactive toys,
and magnetic-stripe readers.
Furthermore, the growing Virtual Peripheral library fea-
tures new components, such as the Internet Protocol
stack, and communication interfaces, that allow design
engineers to embed Internet connectivity into all of their
products at extremely low cost and very little effort.