Amiga Hardware DatabaseCompany GfxBase, USA | Date 1991 | Amiga A2000, A3000, A4000 | Interface Zorro II | Autoconfig ID 2142 / 1,0 |
- graphics card
- GDA = Graphics Display Adapter
- 512 kB or 1 MB VRAM
- the 512 kB GDA-1 is upgradable to 1 MB with four 256k×4 VRAMs
- there is no graphics chip or graphics coprocessor on the card
- screen modes
- 256 colours from the 16.7 million palette
- 640×480, double buffering with 1 MB VRAM
- 800×600, 16 colours with 512 kB, 256 colours with 1 MB VRAM
- 1024×768, 16 colours with 512 kB, 256 colours with 1 MB VRAM
- refresh rate is entirely dependent on the speed of the processor driving the card
- since the display is driven by VRAMs (dual ported DRAMs) the processor will not be slowed down by display refresh like the standard Amiga graphics hardware
- notes
- HD15 VGA connector
- maps its memory directly into the Zorro II address space - limits the amount of fast RAM to 7 or 7.5 MB
- the card can be used as regular RAM expansion when not used for display
- a basic memory mapped frame buffer that is accessible to the programmer as one contiguous memory space
- supported by the X Window System
- does not support standard AmigaDOS screens