louie@trantor.umd.edu (Louis A. Mamakos) (03/23/89)
Now that Amiga systems seem to have large capacity disks on them, it would sure be nice to be able to back 'em up. I would like Commodore to define and (in the case of the 2090 and 2090A) implement a standard interface to a SCSI host adaptor. Here we've got a number of perfectly good SCSI host adaptors, and device drivers that respond to trackdisk.device commands. But we've got no standard way to talk to tape devices. I don't want to solve the problem for just tape devices; what about the guy that comes along with a SCSI scanner or digitizer, or a SCSI attached laser printer? Just think how much easier he could support that hardward if he knew there was a standardized SCSI interface for submitting arbitrary SCSI commands? Given a standard driver interface, the SCSI bus might become the interface of choice for certain types of hardware. If you've got limited resources, develop a product for a SCSI interface rather than an Amiga bus. It will be useful on more platforms. The SCSI interface should be able to support multiple SCSI threads (i.e. a command which has been started, but the target has disconnected), as well as having the Amiga be a *target* on the bus, and not just an *initiator*. Also should a controller be marked as "busy" if a unit on the controller is busy? Or once the controller has disconnected, should I be able to start a command on another unit on that same controller? It seems to me that this is the obvious way to write a driver for a host adaptor; you build a general interface for SCSI commands, and then a trivial device drive that takes trackdisk.device commands and calls on the SCSI driver. My other wish is a Commodore defined standard disk label/partition table on a disk drive. You should be able to specify the size and file system type for each partition, and if a partition should be "automatically" mounted at boot time or not. I'm just full of good ideas, huh? Louis A. Mamakos WA3YMH Internet: louie@TRANTOR.UMD.EDU University of Maryland, Computer Science Center - Systems Programming
steveb@cbmvax.UUCP (Steve Beats) (03/23/89)
In article <3073@haven.umd.edu> louie@trantor.umd.edu (Louis A. Mamakos) writes: >Now that Amiga systems seem to have large capacity disks on them, it would >sure be nice to be able to back 'em up. I would like Commodore to define >and (in the case of the 2090 and 2090A) implement a standard interface >to a SCSI host adaptor. > With the exception of the port to the 2090 and 2090A, what you asked for has already been done. Several SCSI controller vendors contributed to and have implemented the "RigidDiskBlock" and "SCSIDirect" standards. Take a look at the latest V1.3 includes; hardblocks.h and scsidirect.h will describe what you're asking for. Steve