Re: network booting

[Jonno Downes <jonnosan@gmail.com>]

On Jan 11, 10:03 am, "Michael J. Mahon" <mjma...@aol.com> wrote:
> Have you considered using the 2KB I/O bank-switched space at $C800?
> It would give you much bigger "pages".  (And I understand that you'd
> still like to have the Csxx ROM space bank-switched.)
That would be great too. For me the most important thing is there is a
mechanism that is implemented in a standard way in the emulators (or
at least the one I use, i.e. AppleWin :-) and which can also be
manufactured relatively easily. What I want to be able to do is
prototype my firmware in an emulator, knowing that once it's working I
could put it in a real machine as well.

I'm currently playing with 2 emulated devices (having recently moved
houses I don't have access to any of my real 8-bit machines yet). The
2 machines I'm playing with are the A2 via AppleWin and the C64 via
WinVICE. And I've noticed that the WinVICE emulation of the "Retro
Replay" card (which includes the RRNET device, which uses the same
CS8900a ethernet chip as the uthernet) makes some really neat things
very easy to develop - check out for example "the final replay"
cartridge at http://www.oxyron.de/html/freplay.html - this is a C64
cart (more specifically, a BIN file you would load either into the
emulator or into your real Retro Replay cartridge) that gives:
* A m/l monitor (not big deal, the A2 has one built in)
* ability to mount a remote file server as a drive
* BASIC extensions for accessing the network
* CodeNet - a way of pushing or pulling code (or data) into the RAM of
a C64 from a server (i.e. you cand do a code build on your PC and
execute it on a physical C64 without needed to type anything on the
C64 to initiate a d/l)

I'd like to play about with doing something similar on the A2, and so
I need somewhere to put the firmware. Eventually of course it would be
nice to have that firmware on the same card as the uthernet itself
i.e. an "uthernet plus" - which might include some other handy
extensions, such as an NMI pushbutton, an RTC and a circuit that can
be enabled to trigger an IRQ on each vertical blank. These circuits
are all pretty easy to build, and there's plenty of homebrew or even
commercial designs floating about. But they're not standardised as a
platform (either within emulators, or as a card that can be purchased)
such that someone can write some code that uses those circuits and
know that other people have a reasonably good chance of running that
code.

I'm conscious here of the irony of wanting to remove constraints from
an environment which is fun to play with simply because it *is*
constraining - one of the challenges of retro computing is finding
ways to make the platform powerful and easy to use, but not so
powerful and easy to use it's not retro any more. But still, things
could be a *little* bit easier and still be fun I think.

Regards

Jonno