Amiga Hombre chipset
In 1993, Commodore International cancelled the development of the AAA chipset and began to design a new 64 bit 3D graphics chipset based on PA-RISC architecture that would once again bring the Amiga back into the limelight. It had a codename Hombre (pronounced ómbre which means man in Spanish) and was to be developed in conjunction with Hewlett-Packard over an estimated 18 month period.
Hombre was based around two chips: a System Controller-chip and a Display Controller chip.
The System Controller-chip was designed by Dr. Ed Hepler, well known as the designer of the AAA Andrea chip. The chip is similar in principle to the chip bus controller found in Agnus, Alice, and Andrea of the Amiga chipsets. The chip featured:
- A 100 MHz PA-7150 microprocessor
- An advanced DMA engine and blitter with 3D texture mapping and gouraud shading
- 16-bit resolution sound processor with eight voices
The Display Controller Chip was designed by Tim McDonald, also known as the designer of the AAA Monica chip. It is similar in principle to the Denise, Lisa, and Monica chips found on original Amigas. In addition, the chipset also supported future official or third party upgrades through extension for an external PA-RISC processor.
There were plans to port the AmigaOS Exec kernel to low-end systems, but this was not possible due to financial troubles facing Commodore at that time. Therefore, a licensed OpenGL library was to be used for the low-end entertainment system.
The original plan for the Hombre-based computer system was to have Windows NT compatibility, with native AmigaOS recompiled for the new big-endian CPU to run legacy 68k Amiga software through emulation. Commodore therefore chose the PA-7150 microprocessor over the MIPS R3000 microprocessor and first generation embedded PowerPC microprocessors, mainly because these low-cost microprocessors were unqualified to run Windows NT. This wasn't the case for the 64-bit MIPS R4200, but it was rejected for its relative high price at the time.
Hombre was designed as a clean break from traditional Amiga chipset architecture with no planar mode support. Commodore also decided to drop support of the original Amiga eight sprites because at the time sprites became less attractive to developers for its limitations compared to fast blitters. Despite lack of compatibility it introduced newer technologies including:
- A fill rate of 30 million 3D rendered pixels per second. (roughly same as Sony's PlayStation performance)
- 16-bit chunky graphic modes, however there is no 8-bit mode, this way Commodore could keep the cost down by avoiding adding extra 256 color registers for Color LUT.
- 32-bit chunky with 8-bit alpha channel)
- 1280 x 1024 progressive resolution in 16.8 million colors
- One 16.8 million colors sprite (used for mouse pointer)
- 4 playfields at 16-bit graphics mode each
- 3D texture mapping engine
- Gouraud shading
- YUV compatibility with JPEG support
- Standard TV / HDTV compatibility
- 64-bit internal data bus and registers
The chipset could be sold either as a high end PCI graphics card with minimal peripherals ASICs and 64-bit DRAM, or as a lower cost CD-ROM based game system (CD64) using cheap 32-bit DRAM. It could also be used for Set-Top-Box embedded systems.
- Dave Haynie (1995.01.24). "CBM's Plans for the RISC-Chipset". Gareth Knight. Retrieved 31 January 2010. "The initial schedule of 18 months was for the Hombre game machine hardware. There's no real OS here, just a library of routines, including a 3D package, which would probably be licensed. The Amiga OS was not to have run on this system in any form."
- Hombre- The last Commodore custom chipset
- The Dave Haynie Archive with lots of detailed info & specs
- Amiga ReTargetable Graphics
- CD64: Hombre CD32-style console
- Chris Ludwig Interview- Conducted by Amiga News, 1995
- (French) Chris Ludwig Interview
- (French) Article about Hombre
- CBM's Plans for the RISC-Chipset, by Dave Haynie