Serial Advanced Technology Attachment (SATA) is an evolution of the Parallel ATA (PATA) interface that was developed for connecting a host system to peripheral devices, such as hard disk drives and optical storage drives. The need for increased data transfer rates drove the move from a parallel bus interconnect to a serial interconnect. With a 16 bit parallel data bus, signal crosstalk, among other things, became a problem. These problems are resolved by using serial architecture with differential signals instead of a parallel bus architecture. The cabling used with a serial interconnect is less complex and is physically smaller than what is used with a 16 bit parallel bus. A 40 pin cable is required for PATA connections compared to a 7 pin cable for SATA connections, and PATA cables have a maximum length of 18 inches compared to meter or more for SATA cables.  Since the cabling used for serial connections is physically smaller, it allows more flexibility in system design and allows for more storage devices to be installed in the same location without the concern of large bulky cabling.

SATAII

Types of Sata Connectors

SATA 3Gb/s is a second generation SATA interface running at 3.0 Gb/s. The interface supports bandwidth throughput up to 300MB/s and a cable length of up to one meter.

SATAIII

SATA 6Gb/s is a third generation SATA interface running at 6.0Gb/s. The interface supports bandwidth throughput up to 600MB/s, supports a cable length of up to one meter, and is backwards compatible with SATA 3Gb/s interface.

eSATA

External SATA, or eSATA, uses more robust connectors and supports a cable length of up to two (2) meters.

mSATA

miniSATA, or mSATA, was introduced in 2009. Applications include netbooks and other devices that require a smaller solid-state drive. The connector is similar in appearance to a PCI Express Mini Card interface and is electrically compatible.

mSATA SSD on top of a 2.5” HDD
(photo from notebookreview.com)

SATA Express

A new specification, SATA Express, is being developed by the Serial ATA International Organization and combines SATA software infrastructure with the PCI Express® (PCIe®) interface to deliver high-speed storage solutions. SATA Express enables the development of new devices that utilize the PCIe interface and maintain compatibility with existing SATA applications. The technology will provide a cost-effective means to increase device interface speeds to 8Gb/s and 16Gb/s.

CPX1-24 Rugged Mil Grade LCD Display

In the past decade touch screen technology has been integrated into almost every facet of our lives, from smart phones and computer tablets to public information kiosks.  While innovative technologies developed over the past few decades have been tried and tested, many touch screen options don’t work well in the more demanding environments of in-theater military applications or industrial workspaces.

Some of the most commonly used forms of touch screen technology today include capacitive touch, surface acoustic waves, Infrared (IR) Touch, and resistive touch.   There are many other forms, such as optical touch, multi-touch analog resistive (MARS or AMR), dispersive signal, and acoustic pulse recognition, but these are not as widely used. Below is run down of the more popular types of touch screen technology, their benefits and drawbacks, and whether those technologies work or don’t work for rugged use.

Projected Capacitive

Most everyone is familiar with projected capacitive (p-cap) touch as it is used commonly in smart phones and tablets.  This technology has many advantages including the ability to provide excellent image clarity and brightness, withstand heavy use and abuse, and offer multi-touch input.  But for many military and industrial applications, it is has drawbacks. The p-cap touch screen must be touched by a finger or conductive stylus.  In environments where gloves are likely to be worn and styluses are likely to be lost, the potential work disruption is undesirable.  Also, the electric field projected from the touch screen creates an EMI field that can interfere with other equipment or be detectable by hostile forces.  These two factors remove projective capacity touch screen technology as a viable option for most military and industrial applications.

Surface Acoustic Wave (SAW)

This newer technology is competitive because it offers durability and excellent optics.  Like projective capacitive, it has excellent clarity, light transmission, and resolution.  It can also sense pressure as long as you are using a soft-tipped object, which means that gloves can be worn during use. But for rugged applications, it has one major drawback in that it operates by registering sound waves. The device will register false touches due to the vibration that occurs in many industrial and military applications. This makes SAW a technology inappropriate for most rugged environments.

Analog Resistive Touch

Analog Resistive touch is a proven technology with many benefits, including low electromagnetic interference (EMI), low cost and lower power consumption. The touch resolution is very high (typical 4096 x 4096), allowing it to work well with programs requiring written input. Since it is pressure sensitive, the user can input data while wearing gloves or using a stylus, and it reduces the chance of accidental input, e.g., it won’t register a fly landing on the screen.

As with all technology options, there are some minor drawbacks. Only single touches are registered; multi-touch is not a viable option.  Also over time, the touch placement will drift, especially in extreme temperature or high humidity environments.  Periodic calibration of the screen is required, but is a simple and fast procedure.  The resistive membrane also reduces the light emission of the display by about 10%.

Infrared (IR) Touch

IR Touch is also a proven technology.  It has excellent optical properties since there is no overlay over the screen. It supports large screen formats, is extremely durable, and will respond to any input device that will interrupt the light signal crossing over the video screen.  This technology will also support multi-touch, allowing upwards of 10 simultaneous points of input.  There is no EMI generated, and with NVIS Filters it works well for night-vision applications, both important for many military operations.

IR touch can be installed over display surface enhancements such as bonded glass Anti-Reflective (AR) filters.

The only drawbacks would include accidental input and minor pointer drift. The screen doesn’t have to actually be touched for input, only the light grid floating directly above the glass needs to be interrupted, e.g., a fly landing on the screen would register. Also, at very large sizes the cursor can drift near the corners. But the drawbacks are minor relative to the benefits.

What We Choose for Chassis Plans’ Rugged LCD Products

Chassis Plans has recently introduced IR Touch with multi-touch technology for its 24” rackmount LCD monitors, the CPX1-24 and CPI1-24.  This is one of the only multi-touch screen rugged monitors this size in the market. It’s appropriate for military and industrial operations, offers expansive workspace, is extremely high resolution at 4096×4096 points, requires no touch activation force, is sealed to IP65 from the front, and supports multi-touch gesture technology.

Chassis Plans offers analog resistive touch options for most of its rugged LCD products because of its many benefits, including durability and reliability. Our RhinoTouch^® surface technology protects the monitor surface layer from humidity, scratches, vandalism, flames, chemicals, and more.  RhinoTouch^® also provides an option for a finger print resistive oleophobic Anti-Reflective coating.

USB 3.0 Connectors

Universal Serial Bus (USB) has been with us since 1996 and USB 2.0 since 2000.  USB 2.0 has been the defacto standard peripheral interconnect for quite some time.  Now USB 3.0 is out.  Since it’s the newest version of the standard, we might assume that it should be used over the 2.0 standard.  It’s true that 3.0 comes with many improvements over the older version.  However it also has some drawbacks.  Let’s take a look at the major pros and cons of USB 3.0.

You’ll notice from the attached image the enhancements USB 3.0 implements in the connectors.  This allows USB 2.0 devices to plug into the USB 3.0 mating connector.  However, that does not work in reverse.  A USB 3.0 Type B connector will not work with a USB 2.0 Type B receptacle. A USB 3.0 Type A, such as on a thumb drive, will fit in a USB 2.0 receptacle.  Obviously you do not get the speed and benefits of 3.0 from a 2.0 receptacle.

In essence, physically, USB 3.0 is USB 2.0 with additional pins, allowing backward compatibility with 2.0 devices.

Pros

Faster – Yes, as you would expect USB is faster than USB 2.0.  Roughly ten times faster, 625MB/sec vs 60 MB/sec.  Depending on your application, this can be significant.  In many applications, however, this will simply move the bottle neck to another point in the data transfer chain.  The good news is that it is backwards compatible with USB 2.0.  Of course to get the higher speed, USB 3.0 supported devices must be on both ends of the cable.

More powerful – One of the unique advantages about USB is that it provides power as well as data.  And USB 3.0 provides roughly 80% more power than USB 2.0.

Simultaneous bi-directional transfers – USB 2.0 sends data both directions but only one direction at a time.  This is fine if your application shares data one direction at a time.  A thumb drive is a typical device that, for the most part, transfers data either to the drive or from the drive but not at the same time.  USB 3.0 uses a dual simplex architecture which allows bi-directional transfers.  It uses two pairs of data wires instead of one so there is no need to turn the bus around or worry about collisions.

Power consumption – Less power is required to drive the interconnect which means longer battery life or less power draw for systems where power is a premium.

Cons

Cost – The most noticeable drawback is the cost.  Although the 3.0 standard has officially been out since 2008, it still comes at a higher cost.  As a result, many applications that don’t need the improvements of 3.0 continue to implement the 2.0 version.  This slows the adoption of 3.0 and results in the cost staying higher.  It’s expected that the cost will come down assuming 3.0 becomes ubiquitous as most assume it will.

Cable Length – Another downside to 3.0 over 2.0 is cable length.  USB 2.0 support cables of up to sixteen feet in length.  USB 3.0 support cables no longer than ten feet.  However, you can concatenate up to six cable using five USB hubs.  There are also USB extenders for longer runs using CAT5 cabling.

Your Requirements Will Define Your Answer

The good news is that you have USB options for your next system design.  For those motherboards that don’t support 3.0, you can use PCIe boards that provide multiple USB 3.0 ports.  So consider the requirements of your next system and compare the advantages of USB 2.0 vs 3.0 and select the version that’s right for your application.

Chassis Plans provides standard and custom integrated industrial computer systems tailored exactly to customer application requirements and currently offers USB 3.0 support across all their platforms.

Image courtesy of Intel Corporation.

Standard Hard Disk Drives (HDDs) contain one or multiple disks called platters, which are covered in a magnetic coating and then rotated at high speed. Drive heads then move across the platters, changing the magnetization of the material beneath to record data, or reading its state to return the stored information. Solid State Drives (SSDs) by comparison feature a non-mechanical design of NAND flash mounted on circuit boards and contain no moving parts. Rotating media drives have adequate shock and vibration specs but nowhere near SSDs which are shock resistant up to 1500g/0.5ms. The design difference dictates the benefits and drawbacks of each.

Hard Disk Drives vs. Solid State Drives

Hard Drive vs. SSD

HDDs consist of various moving parts such as spinning platters and the read/write heads making them susceptible to shock and damage in rugged environments. The typical failure mode is the read/write head bangs into the platter damaging the magnetic media. Some drives will detect shock events and park the heads but there is still a relatively low limit to the vibration and shock these drives will sustain.  In addition, in a high vibration environment, even though the drive is not being damaged when the heads are parked, neither is the drive able to access the data because the heads are parked.

Because SSD’s have no moving parts, they are as immune to shock and vibration events as any of the other electrical components in a system and are no longer the limiting factor in total system susceptibility and reliability.

SSDs can have (100x) greater performance than traditional “rotating-media” hard drives. That greater performance equates into almost instantaneous data access, quicker boot ups, faster file transfers, and an overall faster computing experience than rotating media drives. This incredible speed difference is due to a much shorter access time (less than a millisecond for an SSD compared to 17 – 18ms for an HDD).

SSDs use significantly less power at peak load than hard drives, less than 2W versus 6W for an HDD. Their energy efficiency can deliver reduced power consumption that translates into less power strain on system itself and a cooler computing environment.

Flash-based SSDs weigh considerably less than hard drives – only 77g versus 752.5g for an HDD. For military and industrial applications the weight savings when using multiple hard drives is significant.

SSD Disadvantages

Though still a higher price/gigabyte than rotating media hard drives (HDDs), SSDs offer cost savings in the long run for projects in the form of with lower energy usage and greater productivity with higher input/outputs Operations per Second (IOPS). One SSD can deliver the performance of 100 HDDs. In 2009, SSDs cost around $3 per gigabyte; today (2013) the cost is now down to $1 per gigabyte.

Another disadvantage of SSDs is that each flash memory cell on an SSD can endure only so many write cycles. This means that if you subject your SSD to heavy use, its data retention will be shorter than with conventional HDD. Luckily, SSD manufacturers are doing all they can to maximize SSD lifetime. They implement various firmware schemes to load-level SSDs and use TRIM technology to maximize the life of a solid-state drive.

Hybrid Solutions

Many of our customers are using a combination of SSDs and traditional hard drives where the operating system runs from the SSD for the speed advantage and the hard drives are used for data storage because of the low cost per byte.

So It Depends on Your Application…

If your application requires a system to be rugged, low power and light weight a solid state hard drive is the perfect storage device for your application.

Chassis Plans offers rugged systems configured exactly to customer requirements including the appropriate selection of rotating media or SSDs.

The Digital Visual Interface (DVI) is a video interface standard designed to provide very high visual quality on digital display devices such as flat panel LCD computer displays and digital projectors. It was developed by an industry consortium, the Digital Display Working Group (DDWG). It is designed for carrying uncompressed digital video data to a display. It is partially compatible with the High-Definition Multimedia Interface (HDMI) standard in digital mode (DVI-D), and VGA in analog mode (DVI-A).

The LCD controllers offered with the Chassis Plans Rugged Keyboards offer DVI-D and DVI-I, depending on which controller is selected. This discussion is presented to help clarify the difference between the various flavors of DVI.

Overview

The DVI interface uses a digital protocol in which the desired illumination of pixels is transmitted as binary data. When the display is driven at its native resolution, it will read each number and apply that brightness to the appropriate pixel. In this way, each pixel in the output buffer of the source device corresponds directly to one pixel in the display device, whereas with an analog signal the appearance of each pixel may be affected by its adjacent pixels as well as by electrical noise and other forms of analog distortion.

Connectors

DVI-D Versus DVI-D

The DVI connector usually contains pins to pass the DVI-native digital video signals. In the case of dual-link systems, additional pins are provided for the second set of data signals.

As well as digital signals, the DVI connector includes pins providing the same analog signals found on a VGA connector, allowing a VGA monitor to be connected with a simple plug adapter. This feature was included in order to make DVI universal, as it allows either type of monitor (analog or digital) to be operated from the same connector.

The DVI connector on a device is therefore given one of four names, depending on which signals it implements:

DVI-D (digital only)
DVI-I (integrated, digital & analog)

The connector also includes provision for a second data link for high resolution displays, though many devices do not implement this. In those that do, the connector is sometimes referred to as DVI-DL (dual link).

The long flat pin on a DVI-I connector is wider than the same pin on a DVI-D connector, so it is not possible to connect a male DVI-I to a female DVI-D by removing the 4 analog pins. It is possible, however, to connect a male DVI-D cable to a female DVI-I connector. Many flat panel LCD monitors have only the DVI-D connection so that a DVI-D male to DVI-D male cable will suffice when connecting the monitor to a computer’s DVI-I female connector.

Essentially, DVI-D is the same as DVI-I with DVI-D missing the analog portion of the signals. A DVI-D connector and monitor can connect to a DVI-I output and function. A DVI-I monitor can connect to a DVI-D output with the caveat that no analog video will be available.

Have you ever owned a computer that made you want to pull your hair out? Wondering if your computer would be on the top 10 list of worst computers of all time? You might be in luck. Chassis Plans, a rugged computer manufacturer, has created this interesting infographic outlining some of the worst computers of all time. From the Commodore VIC 20 to the Netbook, this visual takes you through some of the most loathed computers and the features that drove their owners mad. Name a computer problem and one of these computers probably had it. From slow processor speeds to computers that would turn on in the middle of the night to computers that would melt discs, the problems go on and on. Surprisingly some of these computers, despite their problems set records like “the first commercial computer to be used in space” or “the first personal computer to sell more than one million units.” Check out to the infographic to learn more. Enjoy!

Read more…

Case Study – March 2013

When the end-use of a computer is in a military submarine, that computer has to be designed to withstand shock events to military standards. Submarines, as war craft, are subject to high-levels of shock from collisions or nearby weapon detonation and a submarine computer must be able to handle the blow, while not creating projectiles that could damage other equipment or imperil personnel. Extensive testing is required before such hardware can be installed in this working environment, and this is where Chassis Plans stepped in to help.

Before utilizing our rugged 2U computer in their submarine application, our client needed to verify that the enclosure could pass MIL-S-910D high impact shock tests required by the U.S. Navy. In order to enable our customer to authenticate the ruggedness of the equipment, we provided an enclosure to be used for the various required tests.

High Impact Shock Qualification Test (MIL-S-910D)

As part of a larger rack mount system, our subsystem enclosure was subjected to the High Impact Shock Qualification Test, designed to establish Grade B, Class I, Type A shock qualification as specified byNAVSEA’s General Overhaul Specifications for Deep Diving SSBN/SSN Submarines document, in accordance with Project Peculiar Document (PPD) Requirements for Shock Tests, High Impact Shipboard Machinery, Equipment and Subsystems, as modified by Specifications for Building Submarines, SEAWOLF Class.

The testing performed is meant to simulate an event by mounting a weighted chassis into a rack which is attached to an anvil plate simulating a bulkhead. This is then struck with a 400 pound hammer from a height of 1, 3 and 5 feet from each axis, top, back and side. See the drawing from MIL-S-901D showing the shock apparatus.

Results of the Shock Tests

The Chassis Plans R2U enclosure passed the test without exception and with no required rework or modification. Often this high level of abuse will reveal a chassis deficiency that requires an engineering correction. This was not the case for the Chassis Plans’ enclosure which passed on the first test which validates Chassis Plans design practices and mechanical engineering prowess.

Chassis Plans has over a decade of experience solving customers design requirements. For more information, see some of our other case studies.

Transit Case System for Harsh Environments

Providing our customers with a unique computer system solution is our core business, hence the phrase “Your Configuration.”  But we also sell our systems under “One Part Number.”  This can be a big benefit for customers with projects where multiple components are required to be placed in one rackmount configuration, saving time as well as procurement and labor costs.

Rather than buying system components from several different manufactures and then integrating these components, customers can outsource the entire task to Chassis Plans.  You can order a turnkey portable workstation, which fits your project requirements, under a single part number, all while getting simplified procurement and reducing the personnel hours required for systems integration.  In these times of budget cut backs, and higher costs for larger companies to perform their own transit case integration, outsourcing this service is a cost effective alternative.  It also frees up your time to work on the more complex aspects of your projects.

Tight Trade Show Schedules and Cost Constraints

One Part Number Ordering for Four Integrated Transit Cases

Chassis Plans recently completed a project for a customer that was under limited time constraints for a trade show they were attending in six weeks.  Normally, their procurement department would order the needed systems in many different pieces.  This required separate authorizations for each purchase and the coordination of several different vendors and their associated lead times.  Once all hardware arrived at the customer’s location, it would take several days before the components were received into inventory and routed to the proper location.  Then personnel resources were required to unpack the equipment, execute mechanical assembly, connect power and cables, test, and repack the entire assembly for shipment.   Utilizing these internal resources, the customer projected a nearly three month turn-around time.

By using Chassis Plans to handle the transit case integration, the customer was able to issue one purchase order.  The entire assembly, including transit case, computers, displays and power supplies, were all integrated, tested and shipped within a month. This provided the customer the extra time they needed to add their content, and they were able to deliver the units to the show with time to spare and to stay within their budget constraints.

Integration and Third Party Testing, All in One Part Number

In another situation, a customer required a complete integrated transit case system that required shock and vibration testing for its intended deployed environment.  Chassis Plans provided a complete system tested and approved via a third party test house, and the customer only needed to issue one purchase order.  By working closely with a third party test house, we were able to fine tune the configuration to the customer’s environmental requirements and provide the required certifications.  Chassis Plans was also able to add customer provided content to the systems, further saving the customer time and effort and allowing them to focus efforts on core projects.

One Part Number Saves You Time and Resources

When looking for a rapid, painless procurement of ruggedized computing and display equipment, Chassis Plans can be a valuable partner in this ever changing world of procurement and cost savings.  The outsourcing of rack systems integration saves time, money and most importantly frees up personnel for more important aspects of your projects.