🚀 go-pugleaf

In article <54811.659833076@atronx.ocug.on.ca> rwm@atronx.ocug.on.ca (Russell McOrmond) writes:

> I am wondering if there is a 'memory map' available somewhere that would show
> what is stored where in low memory (Specifically under 1.3, as this is what
> most of the people with problems are running.)
> 
>   ANY information appreciated.
> 
>(Specifically, anyone know what is stored in location $16?  In $217 and $218?)

When I first started programming the Amiga I asked a similar question
of a local guru.  His response was, "Location $4 stores the value of
&ExecBase; all the other locations <1K store the same thing: Nothing
you should TOUCH!"  :-)

Seeing the number of programs that break under 2.0 due to this, I'm
glad I followed the advice.  Actually I had asked out of curiosity.
I'm so paranoid of writing code that will break under future OS's that
I try to forget any "European neat trix" that pop up on the net.

-Tom
-- 
tlimonce@drew.edu     Tom Limoncelli      "Flash!  Flash!  I love you!
tlimonce@drew.bitnet  +1 201 408 5389        ...but we only have fourteen
tlimonce@drew.uucp    limonce@pilot.njin.net       hours to save the earth!"

In article <54811.659833076@atronx.ocug.on.ca>, rwm@atronx.ocug.on.ca (Russell
McOrmond) says:

>(Specifically, anyone know what is stored in location $16?  In $217 and $218?)

The memory from 0 to $400 is the  interrupt vector area, and a map may be found
 in any 68000 book. Most locations are not really used for anything. The only
location defined by the operating system is location 4. The addresses you
mention are pretty much unused and unuseful, so are a result of program bugs.
Typically the only writing that should occur is by debuggers and similar
programs, or by programs taking over the autovectors (which Commodore docs say
you shouldn't do, but some people do anyway. Usually quite harmless).
Hope this clears things up a bit.

-- Dan Babcock

In article <90333.154505DXB132@psuvm.psu.edu> DXB132@psuvm.psu.edu writes:
>In article <54811.659833076@atronx.ocug.on.ca>, rwm@atronx.ocug.on.ca (Russell
>McOrmond) says:
>
>>(Specifically, anyone know what is stored in location $16?  In $217 and $218?)

>The memory from 0 to $400 is the  interrupt vector area, and a map may be found
> in any 68000 book. Most locations are not really used for anything. The only
>location defined by the operating system is location 4. 

And across all possible Amiga configurations, the ONLY thing you can assume is
that location 4 stores the ExecBase pointer.  The vector space isn't really
started at location 0, it's actually relative to the VBR register.  Only, since
68000's don't have a VBR register, they use the default VBR value of 0.  Most
of the time, you don't want to mess with a system vector anyway, since it'll
have a global effect (tasks have a task-private exception vector that's even
easier to use and doesn't muck with anyone else), but if you do, think again
anyway.  If you still do, at least make sure it works on all Amiga systems.

Anything that has to be done like this, at a global level, should NEVER, under
ANY circumstances, become part of an application program, since that is an
operating system job.  If the current OS doesn't support that operation, 
chances are a future one will.  A good example is my SetCPU program.  It did
things that the 1.3 OS didn't properly know about, but it's basically an OS
substitute at that level.  Now 2.0 does most of the same things, and not only
does SetCPU become a little redundant under 2.0, but SetCPU V1.5 (written 
without knowledge of 2.0) doesn't completely work under 2.0.  That's easy to
fix, and I did with SetCPU V1.6, but the last thing you would want is five or
six application programs thinking they could mess with the same things SetCPU
did and all having to be updated now.  One of the major problems with MS-DOS,
more than anything, is that nearly every program out there has to do a large
number of OS level things, since the OS didn't provide for them.  That's a 
heavy load of architectural baggage that forever limits that OS.  The AmigaOS
and 680x0 architecture in general requires a split between application and
operating system functions, but if you support that split properly, all 
applications run on any member of the 680x0 family with a suitably patched
OS behind it.  C= is not going to tolerate the MS-DOS kind of ugliness on the 
AmigaOS, so if you do an OS-type thing in an application, you can expect it 
to break under future OSs.  

>-- Dan Babcock


-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
		      Wheeeeeeeeeeeeeeee...........

Does anyone know if there is a way to get Handshake to let go of the serial
port without exiting so that I can use an external Zmodem download program
to give it Zmodem capabilities?  I like the term, but I hate quitting the
term just to download a file from my account with Zmodem, and I don't like
Kermit, Ymodem, and for sure not Xmodem!  Any help would be appreciated, as
well as if anyone knows when the next version is comming out, and if it will
have Zmodem, and I don't mean that CRUMMY XPR implementation of Zmodem!

Christopher Walton
n074ev@tamuts.tamu.edu

In article <10697@helios.TAMU.EDU> n074ev@tamuts.tamu.edu (Christopher Walton) writes:
>Does anyone know if there is a way to get Handshake to let go of the serial
>port without exiting so that I can use an external Zmodem download program
>to give it Zmodem capabilities? 

	Yes.  With 2.20b, just change the unit number for handshake.  (Haven't
tried it myself, but it should work I think even without another serial
port).

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.commodore.com  BIX: rjesup  
The compiler runs
Like a swift-flowing river
I wait in silence.  (From "The Zen of Programming")  ;-)

In article <16658@cbmvax.commodore.com> jesup@cbmvax.commodore.com (Randell Jesup) writes:
   In article <10697@helios.TAMU.EDU> n074ev@tamuts.tamu.edu (Christopher Walton) writes:
   >Does anyone know if there is a way to get Handshake to let go of the serial
   >port without exiting so that I can use an external Zmodem download program
   >to give it Zmodem capabilities? 

           Yes.  With 2.20b, just change the unit number for handshake.  (Haven't
   tried it myself, but it should work I think even without another serial
   port).

2.20b ? Really ? I thought handshake had stopped at the ubiquitous
2.12 ? I've been using VLT since then, but a new release of Handshake
would be interesting. The VT100 emulation in handshake is still the
best (or should I say, the only working one ?). 

Where can you get it ?

        Carl Edman


Theorectical Physicist,N.:A physicist whose  | Send mail
existence is postulated, to make the numbers |  to
balance but who is never actually observed   | cedman@golem.ps.uci.edu
in the laboratory.                           | edmanc@uciph0.ps.uci.edu

In article <CEDMAN.90Dec19092423@lynx.ps.uci.edu> cedman@golem.ps.uci.edu (Carl Edman) writes:
> The VT100 emulation in handshake is still the
> best (or should I say, the only working one ?). 

I have a VT100 emulator that acts as a filter (converts vt100 to whatever
your terminal uses, using termcap), but it's STILL not quite right. Pretty
close, though... better than most VT100 compatible terminals I've seen. Is
the code to Handshake available?
-- 
Peter da Silva.   `-_-'
<peter@sugar.hackercorp.com>.