CompuServe Thread

#SCSI Interface

1 messages in this thread
#46563From: E. J. Lippert IIJan 1, 1987 5:45 AM
You don't really need to undrestand what Auto-config is, because it is built into your Amiga and nothing you can do can affect it in any way. (That is, as long as you buy add-ons that comply with the Amiga's published Auto-config specifications, everything will work as designed and there will be no compatability problems with future add-ons.) But, if you must know what goes on, here is a brief, simple explanation: When you turn on your Amiga and load KickStart your Amiga will test for devices on the expansion port and if there are any there the Amiga will AUTOmatically CONFIGure them into its memory map. The sequence goes something like this…. Amiga: "Hey is anybody out there on the expansion port?" Device1: "Yeah! I'm here." @@: "What are you?" Device1: "I'm a memory board." @@: "How much room do you need?" Device1: "I need one megabyte." @@: "O.K. I've got room for you from location 300000 to 3fffff." Device1: "Thanks, I'll be one megabyte of RAM starting at 300000." Device1 now is configured and opens the bus to the next device. Amiga: "Hey is anybody out there on the expansion port?" Device2: "Yeah! I'm here." @@: "What are you?" Device2: "I'm a SCSI Hard Drive Controller." @@: "How much room do you need?" Device2: "Not much! 4 bytes or so." @@: "O.K. The smallest space I can allocate is 64K and I've got room for you from location 400000 to 40ffff." Device2: "Thanks, I'll be a SCSI port located at 400000." This sequence goes on until all devices are recognized and configured. E.J. Lippert II C Ltd. Wichita, KS (316) 267-6321