Main Page | See live article | Alphabetical index The A500, also known as the Amiga 500, was the first "low-end" Commodore Amiga 16-bit multimedia home/personal computer model. It was released in 1987, at the same time as the high-end A2000, and competed directly against the Atari 520ST. Technical specifications: Motorola 68000 (32-bit CISC microprocessor with 16 registers lacking MMU for memory protection and virtual memory) Default operating system AmigaOS 1.2 or 1.3 (having 32-bit pre-emptive multitasking microkernel) depending on the revision 512 KB of Chip RAM by default (sound buffers, graphics buffers and software existed in the same memory space) upper limit of 16 MB of memory due to MC68000 limitations (24-bit external address bus) OCS/ECS chipset 50 Hz PAL and 60 Hz NTSC TV output by default versions available; 50/60Hz mode switchable by software software-switchable low-pass audio filter (power LED shows filter status, darker when off) IRQ sharing (like the PCI bus) IRQ system had 7 priority levels of interrupts No limit on number of interrupts available Resources handled by Autoconfig, very similar to ACPI, resources were not numbered or labelled, just given as amounts and addresses No specific I/O ports, instead using memory mapped I/O space separately for each hardware device (thanks to Jay Miner) The A500 designation was also used on an internal Acorn Archimedes development machine. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.