Ok, let's see. I don't have any canned description here, but I'll give it a go. Any more questions, let me know. -Dave Haynie BASIC SYSTEMS The A3000 is a 68030 based personal computer. There are 3 standard base configurations: A3000-16/50 16MHz 68030/68881, 50 Meg SCSI Hard Disk, 1 Meg of Chip memory, 1 Meg of Fast memory. A3000-25/50 25MHz 68030/68881, 50 Meg SCSI Hard Disk, 1 Meg of Chip memory, 1 Meg of Fast memory A3000-25/100 25MHz 68030/68881, 105 Meg SCSI Hard Disk, 1 Meg of Chip memory, 4 Megs of Fast memory MEMORY For those unfamiliar with the Amiga architecture, Amiga memory is divided into 2 groups, Chip memory and Fast memory, both of which are 32 bits wide. The Chip memory is accessible by the Amiga System Chips, which are custom LSI devices dedicated to video display, Bit Image Manipulator ("The Blitter"), Video Coprocessor ("The Copper"), floppy control, serial port, and 4 channel digital audio. This memory, being shared between the CPU and the Amiga chip system, runs slower than the Fast memory from the CPU's point of view, and is generally used only for display, sound, floppy, and serial buffers. The Amiga 3000 supports 1 or 2 Megabytes of Chip memory. The Fast memory system is a 32 bit system dedicated to the 68030 and hard disk DMA controller. This memory supports 68030 cache burst as well as a special "page detect mode", which allows asynchronous 0 wait state performance during contiguous memory accesses. The Amiga 3000 supports up to 4 Megabytes on-board using 256K x 4 Static Column "ZIP" memory devices, or up to 16 Megabytes on-board using 1M x 4 Static Column "ZIP" memory devices. Software support makes it possible to use Page Mode memories instead by disabling the burst and page detect modes. HARD DISK The A3000 system uses the SCSI bus for hard disk access, in conjunction with a custom 32 bit DMA controller. The current SCSI controller chip is designed for SCSI-1, though a pin-compatible SCSI-2 replacement is available. The system is capable of asynchronous or synchronous operation with the SCSI bus at full SCSI speeds. The actual DMA controller buffers incoming SCSI data in a FIFO, mastering the A3000 bus when the FIFO fills to effect 32 bit DMA transfers at full 68030 speed. What this all means, in practical terms, is that an asynchronous SCSI drive going at its full speed of around 1.5 megabytes/second only uses about 3.5% of the CPU time available to the system -- very important for support of multitasking under AmigaOS or UNIX. VIDEO The Amiga 3000 has two video ports, an Amiga standard 23 pin port and a VGA compatible 15 pin port. The Amiga port supplies the full range of Amiga type video, including NTSC (60Hz)/PAL (50Hz) compatible 15kHz modes and VGA compatible modes: Vertical Maximum Horizontal Pixel Horizontal Normal Interlaced Colors Frequency Speed 320 200/256 400/512 64/4096 15kHz 70ns 640 200/256 400/512 16/4096 15kHz 70ns 1280 200/256 400/512 4/64 15kHz 35ns 640 480 960 4/64 31kHz 35ns And with a special monitor 1008 800/1024 N/A 2/greyscale ~50kHz ~22ns All of the color modes have the provision for display into the "overscan" region, which allows something up to 740x480 pixels for a normal 640x400 display mode, with the loss of some hardware sprites (there are 8 total hardware sprites, the last you lose it the pointer sprite). All of the 15kHz modes are translated to 31kHz modes for VGA compatibility at the 15 pin video port. 15kHz modes with 35ns pixels are translated with alternate pixels lost, all others are translated perfectly. There is a single video expansion port inside the Amiga 3000, which permits internal installation of Genlocks and other devices that require access to analog or digital video signals. EXPANSION There are two forms of card-based expansion for the Amiga 3000, Coprocessor and I/O. There is a single 200 pin Coprocessor slot, which is specific to the Amiga 3000, which allows the installation of faster CPUs as they become available. This was designed with the MC68040 in mind, but could be used effectively by alternate processors. Such a Coprocessor card can run in parallel with the A3000's 68030, or it can safely shut down the 68030 and run the entire system itself. Coprocessor cards can share the A3000's system clocks, or they can run asynchronously at their own, faster clock rates. The A3000 system reserves 128 MegaBytes of memory space for use by a Coprocessor board. I/O device expansion, which is usually just called expansion, is standard among all Amiga computers. The original Amiga expansion bus, called the Zorro II bus, is supported, so that all correctly designed expansion cards for the A2000 work in the A3000. The Zorro II bus is a 24/16 bit bus clocked at between 7.09MHz and 7.16MHz. It supports multiple bus masters, shared interrupts, and automatic card configuration (AUTOCONFIG(R)). The Zorro II bus rate is about 3.5 MegaBytes/Second. The Amiga 3000 also supports a new, 32 bit expansion protocol called Zorro III. Zorro II and Zorro III cards may coexist in the same backplane. Zorro III cards support full 32 bit address and data, and the bus is asynchronously clocked -- bus speed depends upon the driving bus master. Zorro III supports multiple bus masters, shared interrupts, vectored interrupts, AUTOCONFIG(R), "burst/block" transfers, and bus locking for multiprocessor support. The theoretical maximum rate on bus is 50 MegaBytes/Second, without bursting; the 25MHz Amiga 3000 drives the bus at approximately 20 MegaBytes/Second. The A3000 implementation reserves 1.75 GigaBytes of address space for Zorro III expansion. SOFTWARE The Amiga 3000 comes with AmigaOS System 1.3 and AmigaOS System 2.0 on disk at the moment. Eventually they plan to freeze the AmigaOS System 2.0 kernel into the A3000's 512K ROM. The AmigaOS provides support for both shell and GUI based user interfaces, lightweight multitasking, shared libraries, interprocess communication, interapplication communication, multiple file systems, and a wide range of other things. Commodore's UNIX system, which currently has no official release date but is well into beta testing, is based on AT&T System V Release 4.0. That includes all the goodies like NFS, X, OpenLook, 680x0 ABI, etc.