Re: Unixisms on top of P8?

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

BLuRry <brendan.robert@gmail.com> wrote:
> On Wednesday, December 19, 2012 7:00:19 PM UTC-6, Bill Buckels wrote:
>> "BLuRry" <brendan.robert@gmail.com> wrote:
>> 
>>> There is one softswitch that cannot be read AFAIK, LCWRITE (which indicates 
>> 
>>> if writes to the language card are enabled or not).  That could make things 
>> 
>>> tricky if you're trying to keep the state 100% correct.  Of course, this is 
>> 
>>> one of those things I would totally love to be wrong about. (like if 
>> 
>>> someone said: "Oh it's not well documented but you can read it at c013" 
>> 
>>> that would be great!)
>> 
>> 
>> 
>> 0x12  - RDLCRAM - Read LCRAM switch state
>> 
>> 
>> 
>> http://vinace.sourceforge.net/en-x1290.html#UnitLanguageCard
>> 
>> 
>> 
>> I don't profess to know anything about this topic... I just did a quick 
>> 
>> google on apple II LCWRITE and this came-up...
>> 
>> 
>> 
>> Bill
> 
> Thanks for the info -- it seems that c012 reads the LCRAM switch which
> determines if ROM or LC RAM will be read.  I'm talking about LCWRITE
> which is a separate mapping for write operations instead of reads. 
> There's no way to know if LCWRITE is set or unset from the 6502 side of things.

There's no way of reading the state directly, but a simple experiment will
determine it. 

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon