[Coco] Re: Newbie help: Barden Bubble w/ Portal-9

[Roger Taylor]

At 10:16 PM 1/28/2004 -0800, you wrote:
Roger:

>This actually clears up a few things for me.  I know this is documented 
>some place and I will eventually find it, but what is the specific address 
>range we should use with ORG in both Portal-9 and a real CoCo?

Since M.E.S.S. emulates the CoCos, the everything works the same.  Portal-9 
just builds software, it doesn't have memory space so you're not loading 
programs into Portal-9 to be run... you're sending your software images off 
to M.E.S.S. which causes them to be run just as if you plugged them into a 
real CoCo (by inserting the disk, or ROM Pak).

BASIC programs occupy rougly the area between 3584 and ~32000.  If a BASIC 
program is loaded, you'll have to load your ML programs into a higher 
address, above the BASIC program (unless you don't care overwriting the 
BASIC program).  Normally, you'll be just loading a ML program into the 
CoCo with nothing else loaded, so try address 3584 so you'll have a lot of 
working room for code and data.

Like I said, in most of my games and programs, I use an origin of 3584 
because I know there won't be any BASIC program loaded at the same address 
or nearby. You could use something like 4000 or even 4096, and it wouldn't 
make a bit of difference in normal situations.  In some advanced 
programming situations, there could be a need for your code to start on a 
certain boundary, such as a 256-byte page boundary, etc.

All of this will most definately not come to you at once, so don't try to 
gather too much at one time.  I highly suggest a CoCo BASIC manual so you 
can study the memory map.



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Roger Taylor