Advanced Amiga Architecture

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Advanced Amiga Architecture (AAA or Triple-A) with 64-bit graphics, should be the successor chipset from AGA . It was supposed to combine contemporary performance with extensive compatibility with the previous Amiga ECS chipset. Since it was foreseeable that AAA would not be competitive with PC graphics cards because of their high costs and low performance, development was discontinued in 1993 in favor of the Hombre chipset. At this point in time, hardware samples of the chips already existed, but they were still very flawed. Three prototypes called “Nyx” were built as a technology demonstration and for troubleshooting.

Among others, Dave Haynie was involved in the development.

Design goals

The AAA chipset should meet these technical requirements:

  • 32/64 bit data bus.
  • 256 deep color table entries, each 25 bits wide (256 indirect colors, indexed via a 24-bit palette with an extra genlock bit as with AGA ). This mode is executed in the native AmigaOS display.
  • Direct 16-bit planes, bit plane pixels without entries in the color table. Since this mode does not use a palette or color table, it requires some kind of ReTargetable Graphics driver like the Chunky mode.
  • New Agnus / Alice replacement chip "Andrea" with an updated 32-bit blitter and copper that can process chunky pixels.
  • A line buffer chip with double buffering called "Linda" offers a 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 to either the left or right channel; each channel has a resolution of 16 bits with a sampling rate of up to 100 kHz; There is also an 8-bit audio sampling input.
  • Direct chunky 16-bit pixels (15 bits for 32768 colors and 1 bit for genlock overlay), implemented in the "Monica" chip, this mode requires an RTG driver.
  • The new 24-bit hybrid mode (with chunky / planar properties) consisted of 3 byte levels with 8 bit blocks each. Like the chunky modes, it needs RTG drivers for the missing color table.
  • New 8/4/2-bit Half-Chunky Graphics mode that works like 8-bit planar modes indirectly through the color table (requires RTG).
  • New packed (compressed) pixels (2-bit PACKLUT and 4-bit PACKHY) that Linda decompresses to 8-bit half-chunky or 24-bit hybrid pixels to speed up animation.
  • A reversible pixel clock for a frame grabber (a video capture device) in chunky modes (this only works with VRAM systems).
  • New Hold and Modify modes (HAM-8 Chunky and HAM-10 for 24 bit / 16.8 million colors).
  • The size of the sprites can go up to 128 pixels in width with any height.
  • Double 8-bit playfields.
  • VRAM chip memory systems with optional 32/64-bit DRAM chip memory (for lower-cost systems).
  • 12 × to 20 × memory bandwidth of the chip RAM access from ECS.
  • Eight times the blitter speed of the AGA / ECS blitter.
  • Direct support for 4MB raw disks (2.88MB IBM formatted and all popular formats including Mac disks), with a direct interface to a raw CD-ROM drive or digital audio tape (DAT) and an digital radio interface, managed by Mary-Chip (port and audio peripheral controller).
  • Asynchronous design, managed by Linda and Andrea, makes the AAA pixel clock independent of its bus clock, so the chipset can work with any CPU (including any RISC processor).
  • In its 64-bit dual system configuration, the chipset would contain up to 1 million transistors (total).
  • Up to 16 MB ChipRAM (graphics memory) in dual systems
  • Two four-byte buffered serial FIFO UARTs, one of these UARTs is in the same RGA address as the original Paula UART.
  • A built-in genlock.
  • 40 on-demand DMA channels dynamically assigned by Andrea.
  • 64-bit pixel bus with 114 MHz pixel clock in dual systems for resolutions of 1280 × 1024 at 72 Hz repetition rate.
  • 128 bit long memory buses.

The initial chipset run was largely functional, but some key parts like the interrupt controller didn't work, others were never tested.

Three prototypes named “Nyx”, which means “night” in classical Greek, were built as technology demonstrators and debugger boards for the new chips. However, Nyx was never intended to be a production version, AAA systems were based on the actuator architecture designed by Dave Haynie.

Commodore filed for bankruptcy before the designs were finalized; Part of the focus on AAA chips has been to develop a radically different 64-bit design based on a modified PA-RISC- 7150 CPU with additional graphics instructions and video pipelines (see Hombre chipset). Fully functional AAA chips were never produced, although they were widely discussed in the trade press. Numerous plans to buy the Amiga and to save the technology came and went after the death of Commodore; all of them including the realization that the development and release of AAA or Hombre would have to be one of their primary goals for the Amiga to remain competitive.

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