More Than Just CPU Performance—Criteria for Choosing an
x86-based Embedded Computer
x86 is a CISC-based structure
that is widely used in embedded computers. Unlike RISC-based
computers, which are designed for specific industrial applications
and to minimize power consumption, x86-based computers are
often used to perform more complicated tasks in a greater
variety of industrial applications. Many users refer to
hardware specifications (such as CPU and memory) and system
performance when choosing x86-based computers. However,
to meet the demands required for different industrial applications,
it is best to choose an x86-based computer with features
tailored to the specific application, but that also works
well as a reliable front-end control unit. As a result,
selecting the best x86-based embedded computer for your
industrial applications can be somewhat complicated. In
this article, we discuss the factors you should consider
when choosing an optimal x86-based embedded computer for
various industrial applications.
Wide Temperature
When x86-based computers are
required to perform more complicated industrial tasks, or
are used in harsh environments, it is important to choose
computers that support a wide operating temperature. To
reduce both power consumption and heat retention, x86-based
computers require a precise hardware design. However, it
can be very challenging for hardware designers to build
a computer that can perform complex industrial tasks without
generating too much heat at the same time.
Hardware engineers can use one of several cooling methods
to control the temperature inside an embedded system for
which the CPU must perform several complicated tasks. These
methods include designing an optimal hardware layout, using
efficient heat sinks, and installing heat pipes to facilitate
heat dissipation. Using the BIOS for dynamic throttling
provides efficient cooling of the system, but also lowers
system performance. Whichever method is used, the ultimate
goal is to keep the system cool while improving performance
for industrial applications.
Designing an embedded computer
that can work in both hot and cold temperatures requires
a tradeoff, since improving the cooling system can make
it harder for the computer to work well in cold temperatures.
One way to get around this problem is to incorporate a self-warming
system, which provides an efficient solution for keeping
an embedded computer warm when the temperature is cold.
All of Moxa's wide temperature embedded computers are required
to pass a 120-hour uninterrupted burn-in and on-off test
to guarantee stable operation in temperatures from -40 to
75°C.
Diverse Peripherals
Since x86-based computers are
often required to perform sophisticated industrial tasks,
support for diverse peripheral devices is an important consideration.
The most common way to interface multiple peripherals, especially
in industrial applications that still rely on legacy equipment,
is with serial communication.
| |
|
| |
1. Serial Communication
|
| |
The RS-232, RS-422, and
RS-485 interfaces are still the most common communication
protocols for industrial data acquisition and transmission.
One of the principal challenges programmers face when
dealing with serial communication is preventing data
loss during data transmission. To solve this problem,
Moxa's patented ADDC® technology guarantees reliable
RS-485 data communication. In addition, the embedded
computer supports non-standard serial baudrates from
50 bps to 921.6 Kbps.
When using RS-485 2-wire communication, one of the most
important factors to determine is when to switch the
transmitter on and off. Because of the restrictions
imposed by the RS-485 interface, only 1 node (on an
RS-485 2-wire bus) can switch its transmitter on at
any given time. A node must switch its transmitter on
in order to send data, and then switch it off after
the last data bit has been sent. |
| |
| |
|
|
| |
• |
There are 2 ways
to switch a transmitter on and off: |
| |
|
1. |
Use
the RTS signal to control the transmitter
"manually by software." |
2. |
Use ADDC®
(Automatic Data Direction Control). |
|
| |
•
|
ADDC® switches
the transmitter on and off "precisely by
hardware," effectively simplifying the complexity
of timing control by software. |
| |
|
|
|
| |
2. Ethernet Ports (Switch
Ports and LAN Ports) |
| |
The TCP/IP protocol suite
is now standard in network communication, and all x86-based
computers are equipped with Ethernet ports for device
communication. However, only computers with multiple
Ethernet ports (switch ports and LAN ports) support
redundancy to ensure network reliability and continuous
operation. |
| |
|
| |
3. Digital and Analog
Input and Output |
| |
DI, DO, AI, and AO interfaces
are commonly used in the security and environmental
monitoring markets. An x86-based computer can serve
as an ideal control unit if embedded with these interfaces. |
| |
|
| |
4. CAN Ports |
| |
The CAN-bus interface is
a common protocol used in industrial automation for
devices running the CAN open protocol. |
| |
|
| |
5. Expansion Slots |
| |
An x86-based computer requires
a large capacity for data storage and processing. The
most commonly used memory expansion interfaces include
SD, USB, and additional HDD sockets. Choosing an x86-based
computer that supports these features makes it easier
for you to upgrade your storage capacity. |
| |
|
| |
6. Modular Flexibility |
| |
As requirements for industrial
applications vary according to the task and field site
conditions, a flexible design that can accommodate different
applications is the optimal solution. For example, some
field sites may require more serial ports and can benefit
from a multiple serial port expansion module. Other
users may need additional Ethernet-based devices that
can be used at the field site; a multiple LAN port expansion
module offers the most cost-effective interface expansion
method.
The modular flexibility of Moxa's DA-682 embedded computer
provides 5 peripheral modules for selection, including
a Universal PCI expansion adaptor for additional peripherals. |
| |
 |
Specific
Certifications for Industrial Markets
Industrial applications generally
require specific certifications to ensure safety and compliance
with industry standards and regulations. When choosing an
x86-based computer, make sure you have taken these industry-specific
certifications into consideration. For example, the power
automation market often requires IEC 61850-3 certification
to ensure full protection for device I/O signals. In addition,
DNV certification is required for x86-based computers used
in marine applications.
Summary
In consideration of all of the
factors that affect reliable and efficient operation in
industrial applications, choosing the ideal x86-based embedded
computer can be a daunting task. Incorporating these simple
guidelines in your selection process can save you a good
deal of time:
- Wide operating temperature
from -40 to 75°C
- Support for various peripheral
communication interfaces including serial ports, Ethernet
ports, DI/DO/AI/AO channels, CAN ports, and expansion
slots
- Modular design for flexible
deployment to meet different application demands
- Certifications for specific
markets, such as IEC 61850-3 for power automation and
DNV for maritime applications
» Back
to index
|
