The Zorro bus is the standard for expansion cards on the bigger Amiga models. One of the main features of the Zorro bus is Autoconfig.
The Zorro bus was introduced with the Amiga 1000. Cards based on the original Zorro bus are not compatible with the later versions.
The 16 bit wide Zorro-II was introduced with the A2000.
Zorro-III had its premiere with the A3000. This 32 bits wide bus was one of the fastest bus systems at the time it was released. It's also downwards compatible with the Zorro-II bus. By multiplexing signal lines, the connectors between the two latest Zorro versions remained unchanged. The Amiga could automatically detect if a 32 bit enabled card was in a slot, and then use the faster Zorro-III mode.
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