steve@dcdwest.dcdwest.com (Steve Meloche) (01/15/91)
Hmmmmm.... I tried this a few months ago and got zero replies. Perhaps
everybody has been too busy namecalling at -MB- to notice my relatively boring
question. Now that the new newsgroups are here I will try again..... Anyway,
here was my previous posting:
Over the course of the Amiga's history, a number of interesting programs
have been developed in the public arena for inexpensively networking amigas
together. The ones I am aware of use DNET as a basis. First there was a
NET: thingy for the serial port (with which I have had only limited success),
then it was modified to work over the parallel port. The big problem for me,
with my A1000, is that I already have three things competing for the parallel
port and one or two for the serial port. What I would like to know is: can
the parallel or serial versions of these networks be modified to use the floppy
drive port with a special cable? Something like the following:
Amiga #1 Amiga #2
.______________. Ext. Floppy Ext. Floppy .____________.
| ._______. | ._________. Special cable ._________. | |
| | Hard | +---+ _____ +-----------------+ _____ +--+ |
| | Disk | | |_________| |_________| | |
| |_______| | |_____.______|
|______________+--- Peripherals (serial or Parallel) |
more peripherals
The floppy port is something that everybody has (I think) and even if an
external floppy is installed it has a pass-through connector, which is not
true of my modem, printer, digi-view, etc. This would work the same way as the
other versions of the NET: device - each Amiga would have access to the devices
on the other machine (even floppies?? - hmmmm... that might be a problem!)
I guess the fundamental question is a hardware one. I have no idea what is on
the floppy port, or even if there is any way for software on the computer to
get the needed access to this port, but I would think it would be possible.
In my mind this means of connection would be much more useful to most Amiga
owners than the serial or parallel port configurations, which steal our
precious ports away. I just can't afford to use them for this reason.
So anyway, net gurus - is it possible? Would it be as fast as the other ports?
Anxiously awaiting replies... (AGAIN!)
Steven Meloche
_____ _____ _____
| ` | ' ` | ' ITT Aerospace/Communications Division
| | | San Diego, CA
__|__ | | dcdwest!network.ucsd.edu!ucsd!... (last I checked)ckp@grebyn.com (Checkpoint Technologies) (01/16/91)
In article <1991Jan14.223623.19008@dcdwest.uucp> steve@dcdwest.dcdwest.com (Steve Meloche) writes: >Hmmmmm.... I tried this a few months ago and got zero replies. Perhaps I don't recall seeing the first try. I should have remembered, because I exlored this possibility myself... To simplify, you ask if some of the available PD/shareware net software (DNET, etc) can be adapted to run on the floppy drive port. Straightforward answer: no. However, if one thinks about the floppy controller as being a serializer/ deserializer, with a data rate (before encoding, which is vital) of 500K bits per second, with a DMA port to chip RAM, with a DPLL for clock recovery even, then one might think that creating a floppy port based network interface would be possible. You'd need a very simple circuit. It would contain device config and select logic, and line drivers for the network. The data rate is low enough to use simple twisted-pair wiring, or phone wires, yet it would be faster than Appletalk. If the line drivers are done right you could hook multiple Amigas together on the same net, rather than being limited to simple point-to-point like DNET and Parnet. And by being DMA driven, the system performance would be high, not at all like a serial or parallel port device which suffers an interrupt for each character. I once considered implementing this and trying to sell them. I have soured on the Amiga somewhat since then, and no longer believe it would make enough to pay for it's development let alone turn a profit. The serial card project convinced me of that. On the other hand, this is the kind of cheap kludge hack that the Amiga marketplace so thrives upon. It would be a good project for the Distillery or Matt Dillon, they don't care whether they make money. -- First comes the logo: C H E C K P O I N T T E C H N O L O G I E S / / \\ / / Then, the disclaimer: All expressed opinions are, indeed, opinions. \ / o Now for the witty part: I'm pink, therefore, I'm spam! \/
jesup@cbmvax.commodore.com (Randell Jesup) (01/16/91)
In article <1991Jan14.223623.19008@dcdwest.uucp> steve@dcdwest.dcdwest.com (Steve Meloche) writes: >I guess the fundamental question is a hardware one. I have no idea what is on >the floppy port, or even if there is any way for software on the computer to >get the needed access to this port, but I would think it would be possible. >In my mind this means of connection would be much more useful to most Amiga >owners than the serial or parallel port configurations, which steal our >precious ports away. I just can't afford to use them for this reason. It's possible (and I think someone in italy has done this). You can access the disk hardware by obtaining access via the GetUnit/GiveUnit calls in the disk resource. You should return an ID code (see the hardware docs) that doesn't conflict with anyone; I'm the clearinghouse for handing out numbers (do NOT chose one yourself, there are a number of ones that are not documented in the hardware manual yet (or ever)). Speed ought to be ~25-30K bytes/sec, you'll have to use MFM encoding so the paula hardware will sync up right to the data. -- Randell Jesup, Keeper of AmigaDos, Commodore Engineering. {uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.commodore.com BIX: rjesup The compiler runs Like a swift-flowing river I wait in silence. (From "The Zen of Programming") ;-)