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Re: NadaNet file server coming soon...
bieling@terra.es wrote:
On Mar 27, 9:24 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
My AppleCrate machines have modified ROMs that replace the self-test
code with NadaNet boot code (published on my web site). When they
power up, they go to into this code, which polls for a boot server.
-michael
A card that looks like a Disk II interface to the autostart ROM should
not be too dificult or expensive to make.
Just drop into it's ROM (would 256 bytes be enough ?) your boot code
and voila !
This way, there's no need to modify the a2, and the card can be moved
around to other IIs as needed.
The AppleCrate places //e main boards about 1" apart, so that
no cards can be plugged in. The absence of conventional I/O
suggested a network boot, which requires a little less than
1KB of code (without any effort at further compression).
Any ROM-bearing card could provide the function to a slotted
machine, but, of course, a boot disk works perfectly well.
I haven't yet needed for a non-'Crate machine without a disk
drive, but it could be useful if you had some machines that
could have a modified disk controller without a drive, but
couldn't have a disk controller *and* a drive.
All of NadaNet, including the "&" interface, fits in about
2KB, so it wouldn't be difficult to skip most of the boot
process on a machine that was so equipped.
There is one problem with network booting--the need to get
a unique number for purposes of communicating (at least enough
to be assigned a "permanent" number). The Apple II doesn't
make the creation of such a number easy without burning
unique ROMs.
The AppleCrate machines no longer have this requirement for
any but the first machine in a hardware daisychain, and it
creates a temporary ID which is larger than any assigned ID--
which is fine as long as there is only one AppleCrate booting
over the network at a time.
As NadaNet is currently configured, the "master" machine only
acts as a boot server during a brief window when the user starts
it, so allowing for machines to boot over the network "at random"
would require a more nearly continuous boot service, which would,
in turn, require a "master" to dedicate some resource to that
purpose.
If I were planning this, I would probably add the boot function to
some other server that runs continuously, like the message server
(which is itself booted from the network!).
-michael
NadaNet networking for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
tool--and it's seriously underused."