AGOCG logo
Graphics Multimedia VR Visualisation Contents
Training Reports Workshops Briefings Index
This report is also available as an Acrobat file.
  Back Next Title

TARGA

Targa (Composite) Targa (RGB)

Manufacturer

Truvision

Appearance

Full length ISA card. 8 or 16 bit slot. This card is unusual in that it extends 30mm above the top of the backplate (instead of the more normal 0-10mm) Jumpers and switches :
  • 1 unidentified jumper
  • 2 banks of 5 DIP switches (I/O base and mode; IRQ)
  • 1 other switch (H/V sync or video out)
The card has a lot of analogue tuning components that are not sealed - beware of fiddlers!

Connectors

  • Internal - VGA feature connector (= 640x480)
  • External - video in and out - not labelled

Installation

Hardware

Slightly troublesome - card guides had to be removed and mounting bracket needed bending I/O connectors not labelled some jumpers had to be set before installation (I/O etc)

Software

The software supplied by the manufacturer was not recommended by the suppliers and extra software, TipsPlus, is usually sold with the card.
  • would like 1MB EMS (expanded memory) û does not provide this information in the software manual.
  • needs an address range excluding (e.g. $D000 for VGA systems), gives start but not range.
  • moved I/O address to $240 to avoid conflict with Soundblaster card.
  • Well worth backing up autoexec.bat and config.sys (of course you do this before every installation already!) as installation routine may (optionally) make quite a few changes to these files (although it does create its own backups).
  • problem setting up EMS for TipsPlus û the Viglen's on board SCSI BIOS resides at $E000-$E3FF and so there is not an uninterrupted 64K page frame available and, naturally, the SCSI BIOS is not relocatable. Fortunately TipsPlus seems to support LIMS (for EMS) 4 so some jiggery-pokery with addresses for 4 x 16K page frames was possible. Even so this did not permit the TipsPlus software to function fully, thus keyboard input appeared on the computer monitor rather than the secondary video monitor that was in this case for image capture (Fig. 3.1)
  • Large range of capture modes (32) available therefore a full assessment was not possible. Chose 768x512 pixels by 16 bit colour (composite and RGB)

    Capture times

    1s

    Observations

    With the setup used in this evaluation (probably more complex than normal) the only mode that would work consistently was 768x512 pixels by 16 bit colour. This was not helped by the need to switch inputs on the TARGA card itself.
    Back Next Title