Detailed Contents
Preface
1 Microsoft Language Utilities
2 Board Installation
3 Operating System Setup
4 Installing Software
5 Configuration Utility
6 Setting up the Video Tape Recorder
7 Other Software
8 Other Hardware
The various issues related to the installation and configuration of the DT-2861 or DT-2862 frame grabber card are discussed in this section. In addition to this installation guide, you may also need the Data Translation documentation for the frame grabber and details of the hardware/software configuration of your computer.
Two of the jumpers (links) on the frame grabber board are required only if a colour video signal is to be digitised. Their purpose is to invoke the filters necessary to remove the colour from the video signal so that only the luminance is digitised. In section 6.3 we recommend connecting only the luminance signal of the Super VHS output from the video recorder. This ensures only a monochrome signal reaches the frame grabber. As a result jumpers W17 (chrominance filter) and W20 (3MHz band width) should be removed. Refer to frame grabber manual for further details.
If you already have a Data Translation DT-2861 or DT-2862 board installed, then there is no need to reinstall this board. You will, however, need to know what the I/O port and memory map address for which the board is configured -refer to the board's own manual for details. If you are not intending on using any Data Translation software, remove or comment out the reference to the Data Translation software driver in your C:\CONFIG.SYS file (removing the driver both increases the available memory and prevents the onboard frame buffers from being cleared if the computer is rebooted).
If the DT-2861 or DT-2862 arithmetic frame grabber board is not already installed, refer to the installation documentation supplied with the board. Make a careful note of any change in the default factory settings for the I/O port or memory map addresses. There is no need to install the Data Translation device driver.
The frame grabber card is mapped into the computer's memory space through a 512KByte window which must be located somewhere in the first 16MBytes of address space. With older computers this limited the amount of RAM to 8 or 12 MBytes as the frame grabber card will not function if RAM occupies the same address space as the frame grabber. However, with the newer "Plug and Play" machines, the BIOS often allows a "hole" to be created somewhere in the first 16MBytes of the address space, thus allowing the frame grabber to be used even if 16MBytes or more of memory are actually installed. The base address of the card may need to be changed from the factory default of 0xA00000 (i.e. starting at the 10MByte mark) to make efficient use of this mechanism (on some machines this hole must be located at the top of the first 16MBytes thus suggesting a base address of 0xF00000 or 0xF800000).
Regardless of how much memory is installed it is essential to ensure that the part of the memory map occupied by the frame grabber must not be cached as both the frame grabber and main processor may access the memory. With the BIOSes in some older machines this may require some adjustment using the computer's setup utility. Plug and Play BIOSes tend to look after this requirement automatically.
Perhaps the most difficult task when installing the frame grabber card is resolving interrupt channel conflicts between the frame grabber card and other cards and devices in the computer. The design of the PC prevents more than one device simultaneously having control over any single interrupt channel. While it would have been easy for the designers to have avoided this limitation, they chose instead to supply PC/AT style PCs with 15 separate channels. In the past this has not been too much of a problem, but as the number of peripherals and cards have increased, 15 is starting to be a problem.
The DT2861 and DT2862 cards are capable of generating interrupts to request immediate action from the computer under some circumstances. As DigImage did not utilise this feature prior to version 1.4, there was no need to activate the interrupt channel, and so no conflicts occurred. However, from version 1.4 the interrupt channel is used in some facilities. In the future the number of facilities using the interrupt are likely to increase, so it is desirable to resolve any conflicts during installation of the card. If it is not possible to resolve the interrupt conflicts, disable the frame grabber interrupts on the card and configure DigImage accordingly. Most of the features of DigImage will still function correctly.
The frame grabber card may be configured to one of four different interrupt channels: IRQ3, IRQ5, IRQ10 or IRQ15. This configuration is achieved using jumpers W10 to W13 (consult the Data Translation documentation for details). It is normally desirable to utilise IRQ15 (factory default) or IRQ10. If neither of these can be made available, then you can use IRQ5. Do not use IRQ3 as this will interfere with the COM2: serial port required for controlling the video recorder. The normal uses of these interrupt channels are given below:
If you are running Windows 95, Windows 98 or a machine with a "Plug and Play" bios, it will be necessary to inform Windows 95/98 that the interrupt is reserved for a specific ISA card. This can be done either at the BIOS level, or using the System group in Control Panel under Windows 95/98.
| Channel | Normal Use | Comments |
| IRQ15 | Reserved | Reserved by IBM, but often used for third party peripherals. In machines with two IDE disk controllers, it may be used for the second controller. |
| IRQ10 | User | Normally available |
| IRQ5 | LPT2 | Second parallel printer port. If only one port fitted, then it should be available. |
| IRQ3 | COM2: (and COM4:) | Do not use as it will prevent proper control of the video recorder. |
Note that it is essential that the interrupt channel selected is reflected accurately in [A Addresses for frame grabber] in the configuration utility (see section 5 )
The method of connecting the video source and display monitor to the frame grabber card is through a connector on the back of the card. Data Translation supply an interface cable as an optional extra. For newer frame grabber cards, the cable is attached via a 15 way D plug. This cable is suitable, but unduly expensive. If you wish to make your own cable, the connections are as follows (looking into the D plug on the card the top left pin is number 8 and the top right number 15):
| Pin | Signal | Pin | Signal |
| 1 | Vertical Drive signal | ||
| 9 | Vert. & Horiz. Drive ground | ||
| 2 | Horizontal Drive signal | ||
| 10 | Composite Blank ground | ||
| 3 | Composite Blank signal | ||
| 11 | Composite Sync ground | ||
| 4 | Composite Sync signal | ||
| 12 | Blue ground | ||
| 5 | Blue signal | ||
| 13 | Green ground | ||
| 6 | Green signal | ||
| 14 | Red ground | ||
| 7 | Red signal | ||
| 15 | Video Input ground | ||
| 8 | Video Input signal |
For older model frame grabber cards, the Data Translation cable consists of the 16-way connector to fit the frame grabber card, an eight-way shielded ribbon cable (in which each of the conductors is separately shielded) and eight BNC sockets. We recommend against using this cable for the following reasons:
We suggest instead that you make your own cable to connect the card to BNC sockets attached to a rigid box. The connector for the frame grabber card is manufactured by AMP connectors (part number 26733-5); alternatively a 16-way IDC may be used. While the AMP connector is designed for the shielded ribbon cable, conventional miniature coaxial cable may be used instead to connect only those signals required - typically only four or five of the eight signals are needed (refer to the manual for the frame grabber card for details). This signal side of the connector corresponds to the component side of the frame grabber card. The shield for the coaxial cable is connected to the other side of the connector.
If you are installing the optional video multiplexer (DT-2859) then we recommend the same method of connecting the video signals. The AMP connector in this case is part number 26733-7.
After installing the frame grabber card in the PC/AT, please run the diagnostic utility DT2861.EXE supplied with the frame grabber card by Data Translation. Note that this utility does not require installation of the Data Translation device drivers. The frame grabber must pass the Acceptance Test in this utility prior to installing DigImage. If the card does not pass this test, please check the address jumpers are correctly set up and consult the frame grabber manual. Note that if the base memory address of the frame grabber has been changed from the default A00000 (this will typically be done to allow for more than 12MBytes of installed memory), then when you specify the new address in the diagnostics utility, specify only the first four hexadecimal digits (e.g for F80000, specify F800). If problems persist, please contact Data Translation or DL Research Partners.
The ideal monitor to connect to the frame grabber card is a long persistence RGB monitor designed to work with a standard interlaced video signal. Such monitors are often used in the broadcasting industry, but are frequently very expensive. A reasonably priced alternative until recently were monitors designed to work with home computers such as the Atari ST and Commadore Anigma. These CGA standard monitors have largely been replaced by much higher resolution PC monitors which, unfortunately, are seldom able to cope with the relatively low refresh rates and interlaced signals of standard video.
The alternative is to use a television set as the monitor. Many modern television sets have the ability to accept a video frequency RGB signal, even though this is seldom of use in the domestic market. One common standard for connecting such a television, at least in Europe, is a SCART connector. Figure 1 shows the connections which may be required. The connector is viewed looking into the socket.
DigImage documentation page
DigImage home page
Stuart Dalziel's home page