Re: NadaNet uses pushbutton1

["Michael J. Mahon" <mjmahon@aol.com>]

Martin Doherty wrote:

> I was just taking my second look at the NadaNet resources on your 
> website.  I note that the protocol uses Annunciator 1 and Button 1.  Is 
> that as in Button 0, 1, 2? Is there some reason why you selected Button 
> 1 instead of 2?

Yes, as in PB0, PB1, and PB2.

I chose PB1 because PB0 is the Open-Apple key, and it is used much
more frequently than PB1, the Closed-Apple key.  PB2 was out because
it is used (by default in newer machines) for the shift key 
modification, which
is very frequently used.

In some ways, it's a shame that Apple "commandeered" all the PB inputs
for other uses after the ][+, but, in practice, I find that PB1 causes
very few conflicts.

The effect of sharing PB1 with Closed-Apple is that by pressing
Closed-Apple you can effectively block network access to that machine.
It doesn't cause any effects on the network, because the NadaNet adapter
drives PB1 with an emitter follower, and the base-emitter junction
effectively isolates the network from the Closed-Apple key.


> I ask because I was imagining a NadaNet app or game that made use of 
> joystick input (Buttons 0 & 1) and it seems to me that this would cause 
> a conflict with NadaNet comms.

There is no conflict as long as you aren't playing the game at the
same time that you are using NadaNet.  There is, of course, the
"standard" problem that pushing the joystick button corresponding
to PB1 at the same time you press Closed-Apple will short the +5v
supply to ground!  ;-)

I'm glad to hear that you are considering NadaNet for your own use!

(BTW, it doesn't do any good to email your post to me when your
email reply address is at "undisclosed".  ;-)

-michael

New Applesoft BASIC interface for NadaNet networking!
Home page:  http://members.aol.com/MJMahon/