White Paper Graphics for SIMATIC IPC

SIMATIC PC

Graphics for SIMATIC IPC -

Technique and advantages

White Paper · April 2011

• Begriffe wie Auflösung, Farbtiefe, Bildfrequenz ren

• Technische Eigenschaf-ten der bei SIMATIC PC eingesetzten Grafikchips zeigenkeiten von SIMATIC PC für mehr als einen Monitor zeigen

•

Answers for industry.

SIMATIC IPC “Graphics for SIMATIC IPC” - White Paper April 2011

About this document: This White Paper provides you with the answers to the following questions: - What do terms such as resolution, color depth and refresh rate mean? - What are the technical properties of the graphics chips used in SIMATIC IPC / HMI IPC? - How can I connect more than one monitor to a SIMATIC IPC / HMI IPC? - What does the term "bandwidth" mean in this context and what are the differences between

PCI and PCI Express? Note: The information provided in this documentation contains merely general descriptions or performance characteristics which in case of actual use do not always apply as described or may change as a result of further development of the products. An obligation to provide the respective characteristics shall only exist if expressly agreed in the terms of contract. Publisher Siemens AG Sector Industry, Industry Automation, Industrial Automation Systems 90475 Nürnberg Germany Additional support Your local Siemens representatives and offices

SIMATIC IPC on the Internet

Information about SIMATIC IPC on the Internet:

http://www.siemens.com/simatic-ipc

You can find your local SIMATIC partner at:

http://www.siemens.com/automation/partner Siemens IA & DT Mall for configuring and ordering your individual SIMATIC IPC: http://www.siemens.com/automation/mall

Copyright © Siemens AG 2011 I IA AS All rights reserved 2 of 27

http://www.siemens.com/simatic-ipc

http://www.siemens.com/automation/partner

http://www.siemens.com/automation/mall


Table of contents

1 Monitors ...........................................................................................................................4 1.1 Resolution, color depth and image refresh rate........................................................ 4 1.2 Screen diagonal and aspect ratio.................................................................................. 5

2 Transmission of graphics data ..................................................................................7 2.1 VGA – Video Graphics Adapter...................................................................................... 7 2.2 DVI - Digital Visual Interface ........................................................................................... 7 2.3 DisplayPort .......................................................................................................................... 9 2.4 HDMI - High Definition Multimedia Interface ............................................................ 10 2.5 LVDS – Low Voltage Differential Signaling............................................................... 10 2.6 UDI - Unified Display Interface ..................................................................................... 10 2.7 Summary and outlook .................................................................................................... 11

3 GPU - Graphics Processing Unit .............................................................................12 3.1 History ................................................................................................................................ 12 3.2 Plug-in graphics card in comparison with onboard graphics chip .................... 12

4 Graphics for SIMATIC IPC .........................................................................................14 4.1 Graphics chips, number of displays and resolutions for SIMATIC IPC ............ 14 4.2 Monitors for industrial use: SIMATIC Flat Panel, SIMATIC Thin Client and SCD Monitor ........................................................................................................................................... 15 4.3 Two or more monitors connected to SIMATIC IPC................................................. 16

4.3.1 SIMATIC IPC with DVI-I connection ......................................................................................... 16 4.3.2 Two monitors connected to Rack PC SIMATIC IPC547C ..................................................... 16 4.3.3 Add-on graphics cards ................................................................................................................ 17

4.4 Display options, scaling and prevention of simultaneous operation ................ 19 4.4.1 Display options............................................................................................................................. 19 4.4.2 Scaling........................................................................................................................................... 20 4.4.3 Operating channel interlocking .................................................................................................. 21

4.5 Remote solutions for SIMATIC IPC ............................................................................. 22 4.5.1 Monitor extension ........................................................................................................................ 22 4.5.2 Thin client technology ................................................................................................................. 23

5 Notes: Required bandwidth for image data transmission................................24 6 Notes: bus systems ....................................................................................................25



1 Monitors

1.1 Resolution, color depth and image refresh rate

The purpose of a computer screen or monitor is to display information from the programs running on the connected PC. This information includes, for example, status messages during the startup of the computer (BIOS) as well as complex graphical representations of every kind of data. As a rule, the graphics data is prepared by a graphics chip that calculates the necessary display information for the representation on the monitor. The graphics information is transmitted between monitor and graphics card by means of analog or digital signals signale over a cable connection. Screen resolution: In exactly the same way as television sets, color monitors create all the visible colors from a mixture of primary colors, e.g. red, green and blue (RGB). A combination of the three primary colors, when viewed from a certain distance, produces a dot – called a pixel – in the required color. The picture on a computer monitor is composed of thousands or even millions of such pixels. The number of pixels available horizontally and vertically, or simply the total of all pixels available is misleadingly referred to as the screen resolution, e.g. 1024 x 768 (pixels) or 2 megapixels. The specification of the pixels, for example as 1024 x 768, is also termed as the "native resolution" of a display. The screen resolution is actually described by the number of pixels per linear unit and is given in pixels or dots per inch (dpi). By way of comparison: a standard computer monitor has approx. 75 dpi, a normal black and white laser printer prints with a resolution of 600 dpi and a color photograph has more than 2000 dpi. From this, it is already clear how inadequately a monitor can represent a real environment. This specification is frequently used as an indication of quality, as it specifies the real size of the pixels and thus the fineness of the screen display. The more pixels that can be represented on the surface of the monitor screen, the more information can be packed into this screen. The specification of the resolution alone still says nothing about the overall size of the monitor. For example, a monitor with 1280 x 1024 pixels could be either a 17" monitor or a 19" monitor. It is just that the size of the individual pixels on the 17" monitor is smaller than on the larger monitor. Formerly, resolutions could be designated clearly using an abbreviation such as "SXGA"1. This is however becoming increasingly difficult in the case of widescreen resolutions (<>4:3). Color depth: The quality of the color representation is expressed in terms of "color depth". Color depths of 24 bits are usual today, i.e. 8 bits for each of the three color channels. Each subpixel can thus represent 28 = 256 nuances of color. In combination this gives a total of 28 x 3 = 224 ≈ 16.78 million individual colors that can be represented. This depth of color is referred to as "true color"2. In general, the individual gradations 1 SXGA refers, for example, to a screen resolution of 1280 x 1024 pixels and stands for Super Extended Graphics Array

2 Not necessarily a faithful representation of natural colors. As a rule, technology dictates that a monitor displays a different spectrum than that perceived by the human eye. The effects of gloss or sheen, for example, cannot be represented in a lifelike manner.



of color in a true color image are no longer discernable to the human eye. Many graphics cards output graphic data at 32 bits, in which only the addressing of the color information is simpler. The 8 bits of additional transmission capacity remain unused 3. Image refresh rate: In order to represent a dynamic image smoothly on a monitor, the screen content must be refreshed at specific intervals. This interval is known as the image refresh rate 4 and is quoted in Hertz. It describes how frequently the image on a monitor is refreshed. Depending on the technology used, the values range from 50 Hz to more than 100 Hz. At 50 Hz the screen content is refreshed 50 times a second. At a frequency of 50 Hz on cathode ray tube (CRT) screens the image is perceived to flicker and it is not considered to be flicker-free until the refresh rate exceeds about 100 Hz. On LCD screens, depending on the design, a refresh rate of 60 Hz is sufficient to achieve a flicker-free display. Conclusion: Resolution, color depth and refresh rate determine the quantity of data that is transmitted from the computer to the screen in order to create the image (see Section 5). For the exchange of configuration data between monitor and graphics card there is an interface called the display data channel (DDC). If monitor and graphics card both support this interface, as is actually the case with all modern displays and graphics cards, the configuration data of the monitor can be transmitted to the graphics card by means of a serial data channel integrated into the respective connections (see Section 2). The monitor can, for example, transmit information such as resolution and maximum refresh rate to the graphics card even while the system is booting up, so that the operating system of the PC can immediately operate the monitor with the correct parameters. If this interface is not used or is not available, the parameters must be entered manually in the graphics settings of the operating system.

1.2 Screen diagonal and aspect ratio

The screen size is now usually specified in inches ("), as well as in centimetres (cm). The measurement is taken between two diagonally opposed corners of the screen. The size of most monitors for office use today ranges from 19" – 24" (about 48 cm – 61 cm), while particularly in image processing applications, monitors larger than 24" are also used. In industry, building technology and also in the field of handheld devices, on the other hand, significantly smaller displays from 3" – 15" are used for operator control or parameter setting. The specification of the aspect ratio provides further information. Traditionally the most widely used aspect ratio has been 4:3. This format has its roots in the distant past. For a long time, 4:3 was the aspect ratio of cinema films and was commonly used for small photographs. But wider formats such as 16:10 or 16:9 are being used with greater frequency, as they correspond better to the natural field of vision of the

3 Graphics can, however, actually also be saved and transmitted using 32 bits. In this case, the last 8 bits are used for saving the alpha channel that specifies the transparency of a pixel.

4 also called image frequency


http://de.wikipedia.org/wiki/Blickfeld


human eye and permit a more pleasant viewing experience. In addition, this is the predominant format for the reproduction of movies on DVD in HDTV quality. For these reasons, the aspect ratio is being assimilated toward the "widescreen" resolution. Movies from the original celluloid incidentally have a much higher resolution and, in some cases, a completely different format (super-widescreen / IMAX). In the private sector the widescreen aspect ratio of 16:9 has now almost completely replaced the 4:3 ratio for monitors. Depending on the manufacturer, aspect ratios such as 5:4 can also be found, so there cannot be any talk of a universal standard at present. The cell phone and automobile industries, for example, with their high quantity production of small displays, are responsible for a wide variety of external dimensions, resolutions and aspect ratios. Some common resolutions, their designations and aspect ratio: Resolution (pixel) Designation Aspect ratio 640 x 480 VGA (Video Graphics Array) 4:3 800 x 600 SVGA (Super VGA) 4:3 1024 x 768 XGA (eXtended Graphics Array) 4:3 1280 x 1024 SXGA (Super XGA) 5:4 1440 x 900 WXGA+ (Wide XGA +) 16:10 1920 x 1080 HD 1080 (High Definition, HD-TV) 16:9 1920 x 1200 WUXGA (Wide Ultra XGA) 16:10



2 Transmission of graphics data

2.1 VGA – Video Graphics Adapter

The VGA connection has been established since 1987 as an analog image transmission standard between graphics cards and display units. VGA also designates a screen resolution of 640 x 480 pixels (Video Graphics Array). A VGA port simply enables more video data to be transmitted for higher resolutions. The VGA port is so-named because it was launched at the same time as VGA graphics cards. A VGA connector denotes a 15-pin D-sub miniature connector (also known as a D-sub mini interface) with three rows of pins/sockets. The VGA interface is still widely used, but is gradually losing its important status due to the fact that most monitors are now capable of processing digital video signals. LCD monitors using TFT technology, for example, operate internally on a purely digital basis; only CRT monitors can still be driven directly with analog data. The conversion of digital data from the graphics card into analog data for transmission via VGA cableand the conversion back into digital data for display on a monitor is prone to lossinformation and wastes time. In addition, the bandwidth is no longer sufficient for thetransmission of the amount of data required to drive large monitors. The longer the cable, the greater is the loss of quality in the transmitted analog signal and in the final picture. As a rule, this means the cable should be no longer than 20 m. Analog signals can also be transmitted via a DVI-I or DVI-A port, as long as the graphics cards still m

of

ake the analog signals available.

2.2 DVI - Digital Visual Interface

DVI is an interface for transmitting digital video and graphics signals. In the computer sector, this interface is now widely used as a transmission medium for digital video data and, to enhance its compatibility, also offers the option of continuing to transmit analog data. The digital video data is transmitted in uncompressed format in accordance with the TMDS standard5. The operation of a digital monitor via DVI offers excellent picture quality at high resolutions. DVI graphics cards and cables are available in both single-link versions and the more expensive and complex dual-link versions. With a single link it is possible to transmit data for a resolution of up to 1900 x 1200 pixels at a refresh rate of 60 Hz (corresponding approximately to Full-HD). Theoretically, up to 3.7 Gbit/s can be transmitted over a single-link cable. Larger screens or higher resolutions can be driven with a dual-link graphics card. This requires a corresponding connecting cable with more pins. In the case of dual-link, the video data is shared between two TMDS transmitters. This enables resolutions of 2560 x 1920 pixels at a refresh rate of 60 Hz to be handled (approx. 7 Gbit/s). Dual-link graphics cards are generally only found in professional applications at present (for screens larger than 26"). The maximum specified cable length from the signal source to the screen is 5 m. Depending on the data rate, cable quality and design of the interface module, distances of up to 30 m can also be achieved.

5 Transition Minimized Differential Signaling: standard for video signal transmission via DVI and HDMI interface


http://de.wikipedia.org/wiki/Grafikkarte

http://de.wikipedia.org/wiki/D-Sub


Greater cable lengths can be spanned by using DVI amplifiers. There is, however, often a restriction of the transmission rate with these extended cables. DVI connectors are divided into two areas: The digital part with up to 24 pins (shown on the left in the picture below) and the analog part with 5 pins ("cross" or "microcross").

Assignment of a DVI-I interface (24+5): right: the "cross" for analog data; left: the pins for digital data transmission

Plug‘n Play

Clock rate Shielding

Digital (Link 2)

Digital (Link 1)

Analog

There are DVIs for different requirements, each having only the pins and wires required for the specific purpose. For example, a DVI-D cable only has the pins required for digital data transmission and cannot transmit analog data.

• DVI-I (integrated) DVI-I transmits both analog and digital signals in versions 18+5 (single link) and 24+5 (dual link). With a "DVI-I to VGA" adapter it is also possible to operate a monitor with a VGA interface connected to the DVI-I interface, provided the graphics card supports the output of both analog and digital data. In the case of SIMATIC Box and Panel PCs, both digital and analog data are transmitted and this can contain different image information in each case (see Section 4.1).

• DVI-D (digital) DVI-D transmits exclusively digital signals. It is available in 18+1 (single link) and 24+1 (dual link) versions. The DVI extension of the SIMATIC Rack PC 847B is an example of a DVI-D interface (see Section 4.2.1)

• DVI-A (analog) DVI-A transmits exclusively analog signals. This version, however, is seldom used. The interface is available, for example, in a 12+5 version. It can however also have fewer (digital) pins.



2.3 DisplayPort

DisplayPort is a relatively new standardized display interface with considerably extended options. In addition to the "video channels", it offers an "auxiliary channel" that enables additional digital data such as USB or audio signals to be transmitted. In the medium term it will probably supplant the above-mentioned interfaces as the VESA6 standard. DisplayPort enables each display panel to be controlled directly, regardless of whether this is done internally in the notebook or externally in the monitor. The maximum data transmission rate for DisplayPort is 10.8 Gbits/s. It therefore offers more than twice the transmission rate of a DVI single link. With this new standard, even the transmission of high-resolution screen contents presents no problems.

It has a mechanical latch (see Fig. on left: the two lugs at front of connector) so that the plug is firmly connected to the socket. This is a key advantage over the HDMI connector that is sensitive to mechanical influences. A further advantage of the DisplayPort is the significant reduction in the number of connecting wires compared to the standard LVDS (see Section 2.5). The DisplayPort connector is significantly smaller than a DVI connector and is therefore more suitable for portable devices and graphics cards with two

outputs and also makes it easier to feed the corresponding cables through monitor support arms or other openings in the industrial environment. The DisplayPort is "function-compatible" not only with VGA and DVI, but also with HDMI. A relatively simple adapter is sufficient for the connection. The current Version 1.1 of DisplayPort also supports the HDCP (High Bandwidth Digital Content Protection) encryption procedure that enables digital signals to be transmitted uncompressed and encrypted. Version 1.2 will extend DisplayPort to include features such as an integral data channel (USB 2.0-compatible data packets). This will enable a touchscreen display or webcam to be integrated without a separate USB cable. In addition, "daisy chaining" will be supported. This allows additional monitors showing the same or a different picture to be linked to the first one. The maximum cable length without an amplifier is 15 m. VESA regards DisplayPort more as a supplement to the HDMI port than as a direct competitor.

6 Video Electronics Standards Association



2.4 HDMI - High Definition Multimedia Interface

HDMI is a digital interface for the transmission of (copy-protected) high-resolution digital video and audio data with a high bandwidth between a digital source (tuner, recorder, player) and a digital output device (flatscreen, speaker, projector). In other words, it originates from the consumer electronics sector. An HDMI port can also be found on many modern laptops and graphics cards, however, by means of which video signals can be displayed on a large flat screen, for example. HDMI is downward compatible to DVI. This means that DVI signals can be transmitted via HDMI using an adapter. It is not possible to transmit HDMI signals in the other direction via a DVI connection. HDMI offers transmission rates of up to 10.2 Gbits/s for a cable length of up to 15 m. The transmission link can be extended by inserting repeaters.

2.5 LVDS – Low Voltage Differential Signaling

The LVDS interface is still frequently used if a display is connected within a system. A typical example would be notebooks, but also the panels of the SIMATIC Panel PC are connected to the system by means of an LVDS interface mounted on the mainboard. One advantage of the LVDS interface is its high data transmission rate (up to 7 Gbits/s or more, depending on the design of the interface), connected with a relatively low emission of electromagnetic "noise" and low power consumption. In many LCD monitors, LVDS is the internal standard for data communication, so that no time is lost here converting the signals. In future, this interface will be replaced by the DisplayPort (see Section 2.3).

2.6 UDI - Unified Display Interface

At the end of 2005 a Special Interest Group (SIG) composed of leading PC manufacturers proposed the development of a new display interface standard. Following the withdrawal of support for UDI by key members of the SIG in 2007 and as the UDI web servers are no longer accessible, UDI can arguably be regarded as an abortive project.



2.7 Summary and outlook

Apart from the necessity of transmitting ever greater quantities of data for larger or higher resolution screens, one of the main driving forces behind the introduction of new interfaces is the film industry. This demands the possibility of encrypting the transmission of copyright material in order to prevent unauthorized tapping of video and audio signals and also to supply large screens with high-resolution images. DVI only offers inadequate options for this. The HDMI interface has its roots in this industry and is also already widely established in the PC market, whereas the new DisplayPort is geared toward the demands of the PC industry and has yet to prove itself or become established. DisplayPort only integrated the compatibility with HDMI as an afterthought, in order to establish the broadest possible basis for the future marketing and acceptance of the interface. For applications with standard screen sizes, DVI is certainly sufficient at present. Especially in the industrial sector, where the transmission of encrypted signals from PC to display (still) does not play a key role, DVI will surely continue to play an important role due to its already widespread use and will only gradually be superseded by the DisplayPort. The miniaturization of the modern DisplayPort and HDMI connectors accommodates the current demands for flexibility and compact computers. For HMI devices with extended functions, such as touch sensors, function keys, data readers, audio devices etc., DisplayPort in its new specification offers good possibilities for connecting such devices with one cable. In this respect, DisplayPort will be able to offer the greatest customer benefit.

Plain to see: the miniaturization of the newer HDMI and DisplayPort digital connectors for graphics output. From left to right: DVI-D, HDMI, DisplayPort



3 GPU - Graphics Processing Unit

3.1 History

In every computer a special chip – the "graphics processing unit" (GPU7) is responsible for the creation of the graphics data. It generates the screen output on the basis of the data specified by the central processing unit. Graphics processing units have been around since the 1980s, although in the early days they had no computational function of their own, but were solely responsible for forwarding the data supplied by the central processing unit. The mid-1990s saw the beginning of the phase in which complex graphics calculations were increasingly relocated from the CPU to the GPU. Today, all graphics calculations can be performed by a specialized chip on the GPU. This chip can perform its duty either on a plug-in graphics card or on the main board.

3.2 Plug-in graphics card in comparison with onboard graphics chip

Compared to onboard solutions, plug-in graphics cards offer the advantage that the graphics chip can be selected according to its purpose, whereas onboard chips are generally more "all-rounders". The market today offers a series of specialized graphics cards for the expansion of computer systems. Probably the best known are the 3D cards for computer games, which are aimed primarily at the fast calculation of 3D objects and effects. Compared to onboard solutions, external graphics cards are normally more powerful, as they use their own high-speed memory and more powerful processors. These processors, however, also have higher power consumption and therefore generate more waste heat. They usually require an active fan which in turn consumes power and is a possible source of faults. On the other hand, onboard solutions are generally more economical because they are integrated into the chipset of the motherboard and have been offering sufficient performance in the 2D sector for many years. These chips are also well suited to industrial applications that put little emphasis on high-speed 3D calculations or special requirements, as the generation of waste heat and the power consumption are lower than for most external graphics cards. These generally do not require their own fan, as passive cooling by means of cooling fins or similar is sufficient. These aspects are particularly important in fanless systems. Furthermore, onboard graphics chipsets are generally available for longer than most external graphics cards and are therefore indispensable for the long-term availability of the overall system. Many integrated graphics chips have only a small internal memory or none at all, so that they have to access the main memory of the computer. This limits the amount of memory available to other applications, such as the operating system. Even the required bandwidth for communication between graphics chip and memory on the system bus is no longer available to other applications. Under certain circumstances this restricts the overall performance of the system, which must be taken into consideration, particularly for real-time systems. As a rule, however, no loss of performance will be noticeable. In the case of integrated graphics processing units, Intel is the market leader due to the many office PCs with integrated graphics chips. Other well-known suppliers, in particular for external graphics cards, include NVIDIA, ATI and Matrox.

7 cf. "CPU" - central processing unit



Due to the vast number of graphics solutions on the market, the table below can only offer a very approximate indication of the advantages of each solution:

Plug-in graphics card Onboard graphics chip

Current consumption - + Waste heat - + Flexibility + - Performance + - Ease of service + - Price - + Main memory requirements + - Noise generation - + Ruggedness - + Availability - +

Important: In this context it should again be pointed out that the waste heat generated by plug-in graphics cards must be considered when designing the ventilation of the device to prevent the temperature within the computer housing from reaching inadmissible levels. Furthermore, before using a plug-in graphics card, it is necessary to ensure that the power supply unit can provide the necessary current and that the maximum permissible output of the power supply unit is not exceeded.



4 Graphics for SIMATIC IPC

4.1 Graphics chips, number of displays and resolutions for SIMATIC IPC

Microbox IPC427C

HMI IPC477C / IPC577C

IPC627C / IPC827C /

HMI IPC677C

Rack IPC547C

Rack PC IPC847C / IPC647C

Add-on card for Rack PC IPC847C / IPC647C

Add-on card for rack IPC547C

Chip Intel GMA

X4500 Intel HD Graphics

Intel GMA 4500

Intel HD Graphics

NVIDIA NVS 295

NVIDIA NVS 290

Memory up to 512 MB 8 bis 256 MByte up to 256 MB 32 MB bis 1,7 GByte

256 MB 256 MB

Memory type shared shared shared shared dedicated dedicated

Outputs DVI-I DVI-I

VGA (DVI-D via extension adapter)

DVI-I

DisplayPort (up to two

monitors, via adapter VGA

or DVI-D)

DMS-59 (one or two monitors via

Y-cable, VGA or DVI)

Max. no. of displays

1 (2 via Y-cable with Microbox)

1 (2 via Y-cable with Box PC)

1 (2 with

adapter)

2 via Y-cable, 4 with add-on

card 2 2

Max. analog resolution Color depth Frequency

1920 x 1200

32 bit 60 to 120 Hz

1600 x 1200

32 bit 85 Hz

2048 x 1536

16 bit 75 Hz

2560 x 1600

16 Bit 60 Hz

2048 x 1536

32 Bit 75 Hz

2048 x 1536

32 bit 75 Hz

Max. digital resolution Color depth Frequency

1920 x 1200

32 bit 60 Hz

1600 x 1200

32 bit 60 Hz

1600 x 1200

32 bit 60 Hz

2048 x 1536

32 Bit 60 Hz

DP: 2560x1600 DVI: 1920x1200

32 Bit 60 Hz

1920 x 1200

32 bit 60 Hz

Cooling passive passive passive passive passive passive

SIMATIC IPCs generally contain an Intel onboard graphics chip integrated into the mainboard chipset. In the case of the Microbox PC SIMATIC IPC427C / Panel PC HMI IPC477C and IPC577C this is the Intel® GMA X45008, whereas in the Rack PC SIMATIC IPC547C it is the Intel® GMA 4500 and for all other SIMATIC IPCs it is the Intel® HD Graphics with Dynamic Frequency. The onboard graphics chips accesses the main memory of the respective SIMATIC IPC (shared memory), where it occupies dynamic memory, depending on the memory configuration. This should be taken into account in memory-critical applications. As an all-rounder, the integrated graphics chip is very good for the calculation and representation of 2D data. The 3D performance of an integrated graphics chip is sufficient for basic 3D calculations, but does not compare with the latest commercially available graphics cards with declared 3D functions. Many graphics expansion cards require an additional power supply in order to cover their high power requirements9. SIMATIC Rack PCs provide a power cable for plug-in graphics cards.

8 GMA: Graphics Media Accelerator

9 Some external graphics cards at full load consume over 200 Watts. This is more than can be supplied via the power supply of the PCIe bus.



4.2 Monitors for industrial use: SIMATIC Flat Panel, SIMATIC Thin Client and SCD Monitor

SIMATIC Flat Panel SIMATIC Thin Client SCD Monitor Display size – Touch – Key

12“ – 19“ optional optional 12" and 15"

10" and 15" yes

19" wide yes

Resolution 800x600 – 1280x1024 640x480 – 1024x768 1440x900 Graphics interface DVI/VGA (Graphics data via

Ethernet) DVI/VGA

Max. distance from operating unit

30m (optional via DVI) - 100m (direct cable connection, virtually unlimited in networks) - Virtually unlimited via Internet

5m

USB device connection optional yes no Design Built-in unit; swivel

arm mounting (15" and 19");

Built-in unit; swivel arm mounting (15");

Built-in unit

Other features cULus; CCC Optional: marine approvals; ATEX 22

cULus; PROFINET basic services

cULus; CCC pending

SIMATIC monitors: For further information on remote HMI solutions using flat panels and thin clients, see Sections 4.4 and 4.5.



4.3 Two or more monitors connected to SIMATIC IPC

4.3.1 SIMATIC IPC with DVI-I connection The DVI-I connector enables two video signals (analog and digital) to be output via one adapter. Using an appropriate Y-adapter (see Fig.) from Siemens, two monitors can be connected to a Microbox PC, Box PC or Rack PC. It should be noted that the signals are split via the adapter cable and that only the digital signal is output via the DVI-D connector and only the analog signal at the VGA output of the cable. Both monitors can then be operated either in the "Extended Desktop" or "Display Clone" mode (for explanation of the modes, see Section 4.4.1). Additional drivers do not have to be installed, as Windows itself already provides this support for the graphics chips in the form of integrated Intel drivers. In the case of SIMATIC Panel PCs, an additional analog or digital monitor can be connected via the existing DVI-I port.

SIMATIC Box PC 627B interfaces: DVI-I interface (blue) for the connection of an analog or digital monitor, or two monitors (1x analog, 1x digital) via Y-cable (available as accessory).

4.3.2 Two monitors connected to Rack PC SIMATIC IPC547C

This SIMATIC Rack PC is equipped with a VGA port for the connection of an analog monitor. A DVI extension adapter can additionally be ordered as an option. This adapter permits the connection of two monitors to the Rack PC with the same functionality as for other SIMATIC IPCs (one DVI and one VGA monitor; extended desktop and display clone; see Section 4.4.1). The adapter occupies the PCIe x16 slot on the mainboard.



4.3.3 Add-on graphics cards In order to improve the graphics performance, a powerful, system-tested graphics expansion card for the PCI-express x16 slot is available as an option for the rack PCs. This card has a high-performance graphics chip for complex 2D and enhanced 3D calculations. No access is made to the main memory of the Rack PCs.

4.3.3.1 SIMATIC IPC647C and IPC847C:

Here the add-on card also enables the connection of up to two monitors. The add-on card features two DisplayPort interfaces (V 1.1), which can provide the monitor signals either analog (VGA) or digital (DVI-D). Thus, this card enables the attachment of two monitors either via DisplayPort and DVI and/or VGA via adapter. The internal graphics chip has not to be deactivated while using this card. Here up to two additional monitors can be attached. So, for the above named Rack PCs using the two connection of the add-on card, Multi-Monitoring with up to four monitors is possible (via onboard graphics 1x VGA and 1x DVI-D plus via add-on card 2x DVI-D and/or VGA).

Add-on graphics card for Rack PCs SIMATIC IPC647C (top) and IPC847C (below): DisplayPort graphics interfaces (blue) of the add-on graphics card for the connection of up to two displays (DVI and/or VGA) via adapter



4.3.3.2 SIMATIC IPC547C

By means of a separating filter of proprietary design, this permits the simultaneous connection of two monitors over a supplied Y-adapter cable with two DVI-I outputs. This means that any two monitors (DVI and/or VGA) can be connected to this card. The internal graphics chip must be deactivated when using this card. If the Rack PC is ordered with the external graphics card it is supplied with the appropriate BIOS settings, but if the card is retrofitted these settings must be made manually.

Add-on graphics card for Rack PC SIMATIC IPC547C: Proprietary graphics interface (blue) of add-on graphics card fort he connection of two displays (DVI and/or VGA) via Y-cable



4.4 Display options, scaling and prevention of simultaneous operation

4.4.1 Display options The following options are available when operating more than one display10:

• Dual view (extended desktop): Different screen contents can be displayed on two connected monitors. This solution is useful if different screen contents are to be displayed at different locations on a single machine. For example, for two users who require different information. In this case, there is a primary monitor on which the Windows taskbar is located. Program windows can be moved around as required. For each of the connected monitors the resolution, refresh rate and color depth can be adjusted individually. Specific feature for Rack PC SIMATIC IPC647C and IPC847C with optional add-on graphics card: Are two monitors attached to the add-on card and two further to the onboard card via Y cable, all monitors can show different contents. One of the monitors attached to the internal graphics card always is the primary display.

• (Display) clone: The same screen contents are displayed on two connected monitors. This option is useful, for example, if diagnostic data has to be output in a control room and also directly on the machine. In this case, a primary display must be defined on which the resolution and refresh rate for both displays can be determined. Specific feature for Rack PC SIMATIC IPC647C and IPC847C with optional add-on graphics card: Are two monitors attached to the add-on card and two further to the onboard card via Y cable, only the two monitors connected to the add-on card or the two monitors attached to the internal card can be cloned. Thus it is not possible to clone a screen of the external display onto a display attached to the internal card and vice versa.

• Single display: In this case, if several monitors are connected, one monitor

can be selected for displaying the screen data. Specific feature for Rack PC SIMATIC IPC647C and IPC847C with optional add-on graphics card: Are two monitors attached to the add-on card and two further to the onboard card via Y cable, one of the add-on card’s monitors can be selected as active display. From the monitors connected to the onboard graphics card, another one can be disabled independently.

10 When using several operator stations (controllable display units), attention should be paid to the fact that simultaneous operation can lead to problems and should be prevented by an operating channel interlock. This applies in particular to dual-view and clone applications.



With the expansion card, the following options for dividing the screen are possible in the case of rack PCs:

• Horizontal span: In this display option, the Windows screen extends horizontally across two monitors mounted side by side. This is a good option if a program opens a very wide display window and you want to avoid horizontal scrolling, which is useful when visualizing plants. In this case, a primary display must be defined on which the resolution and refresh rate for both displays can be determined.

• Vertical span: In this case the Windows screen extends vertically across two

monitors mounted one above the other. This makes it easier, for example, to view a drawing with an extended portrait format. Here too, a primary display must be defined on which the resolution and refresh rate for both displays is determined.

4.4.2 Scaling If a display is not operated in its native resolution (see Section 1.1), the electronics of the display must scale the graphics data. Scaling has the advantage that, in principle, each resolution transmitted by the graphics card can be displayed so that it fills the entire screen of a monitor with a different resolution, provided the electronics of the monitor can process the received data. One disadvantage of scaling, however, is that under certain circumstances the proportions of graphics and text are distorted when displayed and could become unreadable. Here are two examples: A monitor with a native resolution of 1280 x 800 (16:10) can display an image that is transmitted by the graphics card with a resolution of 640 x 480 (4:3). In order that it fills the screen and not just a small area within the screen, the monitor scales up the received image. In doing so, the sides are not enlarged in a 1:1 ratio, but are distorted in the ratio of 1:0.6. A square that has sides of 100 pixels at the 640 x 480 resolution would then appear after the scaling to 1280 x 800 as a rectangle of 200 pixels in width and 160 pixels in height. In addition, scaling can cause a loss of sharpness if, for example, a black horizontal line at 640 x 480 has a length of 640 pixels and a height of one pixel and is then scaled up. The new line will then be 1280 pixels long, but will occupy 1.6 pixels in the Y-axis. To represent the incomplete pixels in the Y-axis, the display electronics calculate a "hybrid value" that blurs the previously clear edge of the line. Some monitors also scale on a linear basis to avoid distortions and leave a black margin along the unfilled area of the screen. The scaling is used in all graphics modes where a resolution can only be set for one display and the other screen has to scale the image (clone und span). Depending on the microelectronics used, an attempt can be made to remove the distortions, but the quality of the scaled representation will still be poorer than in the "original".



4.4.3 Operating channel interlocking As described above, critical situations can arise if two operators simultaneously work on the same "operating image" at two different operator stations. This can easily result in operating errors. One example: two operators, simultaneously and unknown to each other, modify the same production parameter. This simultaneous operation is difficult for the software configuration to avoid, as it generally cannot distinguish between the operating stations and therefore does not register that it is possibly receiving conflicting inputs. In the case of SIMATIC devices, the software ensures that such operating errors are avoided. In the case of a thin client, this is performed by Sm@rtAccess11. In the case of touch devices, the touch driver (planned) is responsible for this and in the upcoming key devices a dedicated driver is responsible.

11 The WinCC flexible/Sm@rtAccess option makes simple client/server mechanisms available for many panels and multi panels, as well as PCs with WinCC flexible Runtime. These mechanisms are the basis for innovative concepts in HMI and automation tasks.



4.5 Remote solutions for SIMATIC IPC

4.5.1 Monitor extension Regular DVI or VGA connections with monitors only permit a restricted length of cable (see Section 2). This depends on the environment, the resolution and in the case of VGA on the "tolerable picture quality". In the industrial sector in general, the limit of fault-free operation for DVI is reached at about 5m and for VGA at about 20m. At greater distances, a combination of specially shielded cable and amplifiers must be used according to the resolution. In addition to the display section, it should be remembered that a USB connection must also be routed to the monitor in the case of operator panels with touch monitors, for example. The USB standard has specified a maximum cable length of 5m, beyond which a combination of signal-amplifying transmitter and receiver modules must be used. Flat panel monitors – "extended" versions: A combination of external transmitter and receiver modules is only acceptable in the office sector – some of these modules even demand an external power supply. Integrated solutions significantly simplify the construction and ensure a more robust overall system. For example, SIMATIC flat panel monitors are optionally available in "extended" versions that already have an integral receiver for DVI and USB. Matching sets of cables are available as accessories from Siemens, enabling cable lengths of up to 30 m to be safely spanned in the industrial sector. For extensions in excess of 5 m, the USB transmitter module supplied with the cable set must be inserted in the connection. An attachment point is provided for this on SIMATIC Box PCs. Even over this distance, it is then possible to use an optional integrated touch functionality of the SIMATIC flat panels. The integrated USB hub also permits the connection of keyboard, mouse or bulk memory.

Configuration examples with a flat panel monitor

Terminal side of a SIMATIC flat panel monitor in the extended version, showing (from left): Power connection 110/230V AC (or 24V DC – behind a sliding cover in this case), USB-In (≤5 m to processing unit), 2x USB-Out, RJ45 for USB-In >5 m, VGA, DVI



4.5.2 Thin client technology For greater distances, thin client solutions, for example, are of interest. In contrast to the transmission of the picture information via a monitor cable, the picture information in this case is processed in the PC itself and made available by means of the TCP/IP protocol to a client that reconstructs the picture from the transmitted data. Feedback about the cursor position etc. is carried on the same path. In this way, practically any restriction of distance can be overcome via the Internet. As a matter of principle, however, there are also restrictions to a thin client concept. The data rate with which the changes to the screen content can be transmitted is normally limited – especially if this data is transmitted via the Internet. Typical office and industrial applications are perfectly suitable for thin client concepts, whereas moving images (e.g. films) often approach the limits of this technology. As the operating system is responsible for the transmission of the screen contents it is also burdened with the necessary calculations. Moreover, an operative system is a prerequisite, as the picture data can only be processed by a program running under the operating system. The operation of a system that is not running or that is still to be started is therefore not possible. Even the readout or modification of BIOS information in the BIOS itself is not possible, as the image and data transmission only becomes possible once the operating system is running. Siemens offers thin clients in 10" and 15" sizes for installation in control cabinets and a 15" device for mounting on a pivoting arm. The devices feature RDP (remote desktop protocol), Sm@rtAccess, VNC (Virtual Network Computing), SINUMERIK-Protokoll plus Citrix ICA Client and an integrated Web browser and server for remote configuration of the device. For environments with explosive atmospheres, special devices are available: SIMATIC HMI Thin Client Ex (see picture). These can be configured for ATEX zones 1/21 and 2/22.



5 Notes: Required bandwidth for image data transmission

In order to display an image, the monitor requires continuous picture data from the graphics card. This is transmitted via the existing interface (in the case of SIMATIC IPC: VGA or DVI). The term "bandwidth" is used colloquially for the transmission performance, but actually refers to a frequency band. It would be more correct to talk of "data transmission rate". The required data transmission rate is calculated by approximation12 as follows: X-resolution × Y-resolution × color depth × refresh rate = data transmission rate For a 19" screen with a resolution of 1280x1024 and a color depth of 24 bits and 60 Hz refresh rate, this produces the following required data transmission rate: 1280 x 1024 x 24 x 60 = 1,887,436,800 bits/sec ≈ 1.9 Gbits/s This means that this resolution can be transmitted without any problems over a single-link DV cable, for example. Conversely, it is possible to work out the maximum screen resolution for any given data transmission rate: X-resolution × Y-resolution = data transmission rate / (color depth x refresh rate) A single-link DVI with a maximum data transmission rate of 3.7 Gbits/s allows a resolution of up to 1600 x 1200 pixels (approx. 20" monitors) by a safe margin.

12 By approximation, because neither correction bits nor dead-time losses are taken into consideration. There are six additional correction bits; dead-time losses are dependent on cable length, quality and technical properties of the graphics card and monitor.



6 Notes: bus systems

Specifically the calculation of graphics data demands continuous and data-intensive communication between the CPU and the graphics card as well as between main memory and graphics card. Until the 1990s system components were connected via the ISA bus and thereafter via the PCI bus. The bus became a bottleneck, since a standard PCI bus13 only allows up to 133 MBytes/sec of data to be transmitted. Furthermore, all connected components must share the available capacity. For this reason, the AGP14 port was developed which supported direct interfacing of the graphics card to the chipset and thus to the CPU and main memory. This took the graphics card out of the bus system so that the full performance of the bus system was once again available to the remaining system components. With an AGP x1 port up to 266 MBytes/sec of data can be transmitted. The reserves of the AGP port are exhausted with AGP x8 which offers a data transmission rate of 2133 MBytes/sec. Further increases in bandwidth could not be implemented by means of AGP as the physical problems could no longer be overcome. However, graphics cards soon reached the level of performance that brought the AGP port to its transmission limits. In addition, the continued development of the remaining system components, such as audio output, faster drives (SATA) and USB led to a greater demand for available bandwidth on the system bus. For this reason, a PCI Special Interest Group (PCI-SIG) has been working on the development of PCI since 2002 and has now developed PCI Express15. PCI Express should replace both PCI and AGP. In contrast to its predecessors, PCI-Express Version 1.0 is a serial point-to-point connection clocked at 2.5 GHz which, depending on the version, makes a certain number of "lanes" available for the data transmission. A lane comprises two pairs of lines, one each for transmitting and receiving data. Data transmission rates of 250 MBytes/sec per line are possible16. This means that with one PCIe x1 slot a total data transmission rate of up to 500 MBytes/sec is possible (250MBytes/sec for both transmission and reception). If the PCI-SIG gets its way, PCIe x1 will replace the standard PCI slot. In further established PCIe versions, the transmission rate increases by the respective multiple. Accordingly, the PCIe x16 offers a total data transmission rate of 8 GBytes/sec (4 GBytes/sec. in each direction). This interface is also termed "PEG" or "PCI-Express for Graphics" as it is frequently used for connecting external or internal graphics cards. A number of PCIe components can be connected by means of switches.

13 Most widely used: PCI 2.0 with a bandwidth of 32 bits and a clock speed of 33 MHz. 14 Accelerated Graphics Port: not a bus, but a point-to-point connection. 15 Also "PCI-E" or "PCIe"

16 The data is transmitted with an 8B10B coding: 8 bits of data are transmitted as a 10-bit code. At a clock speed of 2.5 GHz, this gives a data transmission rate of 250 MBytes/sec in one direction.



Bus system Data transmission rate Bus type ISA 16 MBytes/sec parallel PCI (32-bit, 33 MHz) 133 MBytes/sec parallel AGP x8 (no bus) 2133 MBytes/sec parallel PCIe x1 500 MBytes/sec serial PCIe x4 2000 MBytes/sec serial PCIe x16 8000 MBytes/sec serial PCIe x1 (V2.0) 1000 MBytes/sec serial PCIe x1 (V3.0) 2000 MBytes/sec serial

Overview of bus systems, data transmission rates and type of bus

In early 2007 the PCIe Version 2.0 was released which doubled the clock speed and thus the data transmission rate. This means that up to 1 GByte/sec of data can be transmitted via one PCIe x1 interface. The next generation – PCIe 3.0 was released November 2011 and doubled the data transmission rate yet again. This is done by raising the clock speed to 8 GHz and at the same time lifting the 8B10B coding changing to a 128B130B coding. One PCIe x1 slot now is capable of transmitting data at up to 2 GBytes/sec.

"Large" SIMATIC Rack PC 847B bus board with 11 expansion slots: From left to right in picture: 3 PCIe x4 slots (black, short), 1 PCIe x16 slot (black, long) and 7 PCI slots (white)




Links to further information: SIMATIC IPC on the Internet: http://www.siemens.com/simatic-ipc Distributed design of SIMATIC HMI Panel PCs: http://www.automation.siemens.com/Industrial-PC//html_00/products/panel_pcs/pc_dezentral.htm Monitors for industrial use: http://www.automation.siemens.com/hmi/html_00/products/hardware/lcd_displays/index.htm Further White Papers on SIMATIC IPC: http://www.automation.siemens.com/Industrial-PC/html_00/support/infomaterial.htm Siemens Industry Automation and Drive Technologies Service & Support: http://support.automation.siemens.com/ Intel Graphics Media Accelerator 950 (de/en): http://www.intel.com/cd/products/services/emea/deu/216821.htm http://www.intel.com/cd/products/services/emea/eng/216464.htm Intel Graphics Media Accelerator 4500 and X4500 (en): http://software.intel.com/en-us/articles/quick-reference-guide-to-intel-integrated-graphics/ Intel GMA Developer Guide (including 4500 and X4500, en): http://software.intel.com/en-us/articles/intel-graphics-media-accelerator-developers-guide/ NVIDIA Quattro NVS (expansion cards for SIMATIC Rack PC): http://www.nvidia.de/object/IO_14605_de.html Registered trademarks Any product names mentioned may be trademarks or product designations, whose use by third parties for their own purposes may infringe the rights of the trademark owners. Copyright © Siemens AG 2011. All rights reserved The reproduction, transmission, or use of this document or its contents is not permitted without express written authorization. Violation of this rule can lead to claims for damage compensation. All rights reserved. Disclaimer of liability We have checked that the contents of this document correspond to the hardware and software described. However, since variance cannot be precluded entirely, we cannot guarantee full consistency. The data in this manual is reviewed regularly and any necessary corrections are included in subsequent editions. Suggestions for improvement are welcome. Subject to change.

http://www.siemens.de/simatic-ipc

http://www.automation.siemens.com/Industrial-PC//html_00/products/panel_pcs/pc_dezentral.htm

http://www.automation.siemens.com/hmi/html_00/products/hardware/lcd_displays/index.htm

http://www.automation.siemens.com/Industrial-PC/html_00/support/infomaterial.htm

http://support.automation.siemens.com/

http://www.intel.com/cd/products/services/emea/deu/216821.htm

http://www.intel.com/cd/products/services/emea/eng/216464.htm

http://software.intel.com/en-us/articles/quick-reference-guide-to-intel-integrated-graphics/

http://software.intel.com/en-us/articles/intel-graphics-media-accelerator-developers-guide/

http://www.nvidia.de/object/IO_14605_de.html

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