Re: network booting

[Jonno Downes <jonnosan@gmail.com>]

On Jan 11, 10:40 am, BLuRry <brendan.rob...@gmail.com> wrote:
>
> (totally possible to do in the Jace emulator, just requires writing a
> class that represents that card)

Nifty stuff - I'm doing an svn co now.
Although having a custom card class would only achieve some of my
goals (i.e. making it easier to develop the firmware code) - the other
part is about being able to make that code available to other people,
knowing their is a way for them to use it either on a real machine or
the emulator of their choice. Still, if it was working properly in
jace it would be easier to convince creators of hardware and other
emulators to do the something compatible.


> > the 74LS273 is wired up with
> >         * CP (clock pulse) connected to inverted /DEVSEL (pin 41 of the bus)
>
> There is a method called motherboardTick that simulates the clock
> pulse.

to clarify - the CP refers to the chip on the 74LS273, i.e. it's the
signal that tells the 74LS273 to latch the output lines to be whatever
is currently on the input lines.  For this circuit it needs to get /
DEVSEL from the Apple (or emulator) not a clock pulse.

>
> >         * /MR (master reset) connect to /RES (pin 31 of the bus)
>
> There is a method called reset that simulates the reset signal

to clarify - this is an input on the 74LS273 - I assume there would be
an OnReset event that the card class would need to implement to handle
when a reset was initiated?

> I built Jace around expandability.  Mostly because I wanted the
> ability to replicate Mame-style cheats, but also because I was feeling
> a little silly when writing it.  (jack and coke does that
> sometimes... ;-) )

neat stuff indeed.

Regards

Jonno