Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!henry.jpl.nasa.gov!elroy.jpl.nasa.gov!ucla-cs!maui!michael From: michael@maui.cs.ucla.edu (michael gersten) Newsgroups: comp.sys.amiga Subject: Re: GVP controller Keywords: DMA is better. Message-ID: <26545@shemp.CS.UCLA.EDU> Date: 19 Aug 89 00:01:39 GMT References: <8908072207.AA14796@jade.berkeley.edu> <12254@grebyn.com> <501@tardis.Tymnet.COM> <1701@cs-spool.calgary.UUCP> Sender: news@CS.UCLA.EDU Reply-To: michael@cs.ucla.edu (michael gersten) Organization: UCLA Computer Science Department Lines: 17 In article <1701@cs-spool.calgary.UUCP> deraadt@enme3.UUCP (Theo Deraadt) writes: > >With a SCSI drive, any of the newer than 2 year ones anyways, the drive >spin time is NOT a factor. You issue a command to the SCSI drive, and then >disconnect from the device. The device has a cache on it. It gets the first >bunch of stuff. Then it reconnects to the controller. This is a good point. What controllers for the amiga support both bus arbitration (multiple computers/initiators on the same cable) and bus selection/disconnect/reconnect? I.e., I want to be able to have a read going on one drive while another drive is busy writting (both on my amiga), while a third drive is in the middle of a command for the other computer. Later, the programs can exchange data over SCSI--or am I hopelessly dreaming? Michael