Advanced Amiga Architecture chipset
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The AAA chipset (Advanced Amiga Architecture) was intended to be the next-generation Amiga multimedia system designed by Commodore International. Initially begun as a secret project, the first design discussions were started in 1988, and after many revisions and redesigns the first silicon versions were fabricated in 1992–1993. The project was stymied in 1993 based on a lack of funds for chip revisions.
At the same time AAA started first silicon testing, the next generation Commodore chipset project was in progress. While AAA was a reinvention and huge upgrade of the Amiga architecture, project
Design goals
AAA was slated to include numerous technologies.
- 32-bit CPU bus
- 32-bit and 64-bit graphics bus options.
- 256 deep display.
- Direct 16 bit-planes CLUT it requires some kind of ReTargetable Graphics(RTG) driver like chunky modes.
- New Agnus/Alice replacement chip 'Andrea' with an updated 32-bit Copper which can handle chunkypixels.
- A line-buffer chip with double bufferingcalled 'Linda' provides higher resolution (up to 1280 × 1024). Linda also decompresses two new packed pixels (PACKLUT, PACKHY) on the fly.
- Updated version of Paula called 'Mary' with 8 voices that can be assigned either to left or right channel; each channel has 16-bit resolution with up to 100 kHzsample rate; additionally it does 8-bit audio sampling input.
- Direct Chunky 16-bit pixels (15 bits for 32768 colors and 1 bit for genlock overlay), provided by custom chip 'Monica', this mode requires RTG driver.
- New 24-bit hybrid mode (with a CLUT.
- New 8/4/2 bit Half-CLUT like 8-bit planarmodes do.(requires RTG)
- New packed (compressed) pixels (2-bit PACKLUT and 4-bit PACKHY) decompressed by Linda to 8-bit half-chunky or 24-bit Hybrid pixels respectively, used for speeding up animations.
- A reversible pixel clock for a frame grabber (a VRAMsystems).
- New Hold-and-Modifymodes (HAM-8 chunky and HAM-10 for 24bit / 16.8 million colours).
- Sprites size can go up to 128 pixels in width with any height.
- Dual 8-bit playfields.
- DRAMchip memory (for lower cost systems).
- 12× to 20× memory bandwidth of Chip RAM access of ECS.
- 8× blitter speed increase of AGA/ECS blitter.
- Direct support for 4 MB raw Mac floppies), with a direct interface to a raw CD-ROM drive or Digital Audio Tape (DAT) and a digital radiointerface, managed by Mary chip (port and audio peripheral controller).
- Asynchronous design managed by Linda and Andrea makes AAA pixel clock independent of its bus clock so the chipset can work with any CPU (including any RISC processor).
- The chipset would include up to 1 million transistors in its 64-bit dual-system configuration (total).
- Up to 16 MB ChipRAM (graphics memory) in dual-systems.
- Two four-byte buffered UART.
- A built-in genlock.
- 40 on-demand DMA channels dynamically allocated by Andrea.
- 64-bit pixel bus with 114 MHz pixel clock in dual systems which makes 1280×1024 @72Hz screens possible.
- 128-bit long memory bus bursts
The initial chipset run has a number of early chip problems. The LUT was scrambled, so while it was possible to put up images on the screen in test systems, it was necessary to run a bit-skiggling[clarification needed] filter that re-arranged the color to work with the existing hardware. There was a bug in the Andrea memory controller that required a FIBed die locked into either DRAM or VRAM mode. There was a bug in the Andrea bus control logic that prevented Andrea's data bus from going tri-state during DMA reads from the other chips. That prevented some important bits of the functionality of the other chips from being tested.
Three prototypes called '
See also
- Original Amiga chipset
- Amiga Ranger Chipset
- Enhanced Chip Set
- Amiga Advanced Graphics Architecture
- Hombre chipset
- List of home computers by video hardware