Cambridge Research Systems

Why do I need a ViSaGe?

Getting from that brilliant insight to the crucial experiment can be the hardest part of any research project. The choices for visual stimulus generation can be bewildering, but false starts waste your time and money.

Computer graphics seem the obvious solution, but it's not always that simple. Most systems are really designed for games: they are difficult for novices to program and unsupported by the manufacturer. Often their dynamic range is limited, with inadequate contrast and colour control for experimental applications, and timing is unpredictable.

You need the ViSaGe advantage:

Real-time driver for Windows guarantees frame-synchronous presentations even at 100Hz+ frame rates
14bit colour and luminance control with integrated support for gamma correction and colour calibration
Dedicated PCI Express framestore to buffer sequences of precalculated images
Integrated digital I/O interface for controlling third-party equipment like electrophysiological amplifiers
Toolbox for MATLAB means experimental scripts are easy to generate; no Windows programming in C is required for most applications!

Specifications

Technical Specification

Graphics engine: x4 PCI Express
Graphics configuration: Dedicated stimulus display (the ViSaGe is not a replacement PC graphics card and does not run Windows)
Video output: 14 bit video DACs; 14 bit resolution per colour channel; 160MHz pixel clock; 200kHz line scan rate; 200Hz frame rate
Display memory: 256MB video memory; configured as 32 bits per pixel; separate pixel and overlay planes
Offscreen memory: Dependent on PC RAM; used for storage of precalculated image sequences

Connectivity

Digital I/O: Ten TTL-compatible inputs; ten TTL-compatible outputs
Analog in: Six inputs, 16 bit, ±5V signal range, 500Hz bandwidth, free running or synchronised to the stimulus display
Analog out: Two outputs, 16 bit, ±5V signal range, updates are frame synchronous
Response box: Built in infra-red receiver; built in speaker for feedback; compatible with CB6 & CT6.
Compatible with FE-1 stereo goggles

Connectors

Video output: DVI-I output for connection to analog stimulus display
Analog I/O: Six BNC inputs; two BNC outputs
Digital I/O: Trigger In BNC, bi-coloured status LED; Trigger Out BNC, bi-coloured status LED; 25 way D connector
Computer interface: USB B input
Ancillary equipment: Dual 5 pin Tyco Triad type 01 circular connectors

Supplied Software

MATLAB: CRS Toolbox for MATLAB (R2006 or later)
Windows programming:VSG Software Library v8.1 for 32 bit Windows
Demonstration programs: For MATLAB, Delphi, C++Builder, Visual Basic; source code provided
Backwards compatibility: Native VSGv6 programs for the VSG2/2, VSG2/3, VSG2/4 and VSG2/5 can be recompiled and run on ViSaGe

Packaging

Framestore: x4 PCI Express card (modified 3DLabs R500 PCIe card)
Control Unit: 280mm x 100mm x 100mm black anodised aluminium tower
Supplied cables: 2m DVI-D video cable for connection between framestore and Control unit; 2m DVI-I to VGA video cable for connection to stimulus display; DVI-I to VGA adapter Windows desktop output; 1.5m USB cable
Software: Internet download only. Register your VSG serial number at our web support portal
Power: Region-specific 7.5V wall mount PSU

Minimum System Requirements

Computer: Dell Precision T3400 Workstation or similar with unoccupied x4 or x8 PCIe slot, one free USB2 port; contact CRS for details of the latest models
Dual displays: SVGA display for Windows desktop (i.e. 800x600 @ 60 Hz), VGA CRT monitor for Stimulus Display (i.e. 640 x 480 @ 60 Hz)
Operating system: Microsoft Windows XP Pro SP2

A comparison of the ViSaGe with legacy VSG hardware versions

Hardware feature

VSG hardware version

ViSaGe PCIe

ViSaGe AGP

VSG2/5

VSG2/4

VSG2/3

PC bus type

4 lane, PCI Express

66 MHz, 64 bit, 4x AGP

33 MHz, 32 bit PCI

8 MHz, 16 bit ISA

Max. transfer rate from PC DRAM

>40 MB/s, plus hardware acceleration

>40 MB/s, no hardware acceleration

4 MB/s

1.5 MB/s

Output resolution

14 bit

15 bit

15 bit, 8 bit

12 bit, 8 bit

DAC system

3 x various manufacturers

2 x ADV7162

2 x Bt460

Graphics processor

3DLabs Wildcat P25

3DLabs Wildcat P9

TMS34020

Graphics processor speed

N/A

50 MHz

40 MHz

Framestore - standard configuration (AKA "VideoPage" memory area)

256 MB

256 MB - [1]

8 MB

4 MB

Framestore - add-on sizes

N/A

24 MB

32 MB, 16 MB

Max. framestore size

256 MB

256 MB - [1]

32 MB

68 MB (2 x 32 MB)

Framestore pixel size

4 bytes

1 byte or 4 bytes

1 byte

VideoPage video modes

8 bit palette
24 bit true colour

8 bit palette

Overlay plane size (AKA "OverlayPage" memory area)

16 MB

2 MB

OverlayPage pixel size

4 bytes

1 byte

OverlayPage video modes

8 bit palette
24 bit true colour

2 bit palette

4 bit or 8 bit palette,

4 bit or 8 bit palette

On-board, non-display memory (AKA "ScratchPage" memory area)

8 MB - [2]

8 MB

4 MB

ScratchPage pixel size

4 bytes or 1 byte

1 byte or 4 bytes

1 byte

ScratchPage video modes

8 bit palette
24 bit true colour

8 bit palette

8 bit palette,

8 bit palette

Local, non-display memory (AKA "HostPage" memory area)

Unlimited - [3]

HostPage pixel size

4 bytes or 1 byte

1 byte or 4 bytes

1 byte

HostPage video modes

8 bit palette
24 bit true colour

8 bit palette,

8 bit palette

Digital I/O

Ten in
Ten out

Eight in
Nine out

Five in
Nine out

Analog I/O

Six 16 bit in
Two 16 bit out

Five 12 bit in
One 12 bit out

Seven 12 bit in
One 12 bit out

Hardware reaction timing
(requires CB6, CT6, CB3 or CT3 response box)

Yes (only CB6, CT6)

Yes

Max. pixel clock

160 MHz

150 MHz

120 MHz

Max. line rate

200 kHz

Max. frame rate

200 Hz

500 Hz

Support for VSGDSP

Yes

Support for RG1, RG2

Yes

Supported in VSG software version

8.1

8, 6

8, 6, 5, 4

Important Notes

[1] - The original ViSaGe framestore was provided on a dual-head AGP graphics card. The framestore memory space was shared between the Windows desktop and the VSG Stimulus Display. This means that some of the 256MB area was reserved for use by the Windows display.

[2] - The ViSaGe on-board, non-display memory space is emulated using main PC memory and is provided only for backwards compatibility. There is no additional benefit in using this memory space compared to the off-board, non-display, virtual memory space.

[3] - The off-board, non-display memory space is a virtual VSG memory area which uses main PC memory. The memory space size is dependent on the amount of free RAM in your PC.