HOW TO IDENTIFY THE MEMORY/EXEC ADDRESSES

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sikorsky76's picture
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Joined: Jul 8 2007
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Hi!

I have a vintage cassette tape program released by subLOGIC in the late seventies. The label says: SUBLOGIC 6502 / APPLE II 3D GRAPHICS. I would like to boot it up on my Apple II+ computer. Can someone assist me in finding the right memory/exec addresses?
Thanks! Marc

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Joined: Apr 11 2006
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Andy McFadden has an interest

Andy McFadden has an interesting discussion of tape protection schemes, which may be of interest:

http://www.fadden.com/techmisc/cassette-protect.htm

In it, he mentions that BASIC (or BASIC-booted) programs could be started with just LOAD. If subLOGIC required you to load into a particular address, then, you'll have to either find docs or someone who remembers. Smile

sikorsky76's picture
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Joined: Jul 8 2007
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Hi! Thanks for the info. I

Hi!

Thanks for the info. I am afraid I will have to find the proper documentation. This program requires to be loaded at a particular address. I wonder if an intelligent sequence could be used to find it...!!! I was able to load the other side of the cassette which is a flight simulation DEMO. The address is 800.2000R 1F00G, it was typed on the casette label.

Marc

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Of chickens and eggs

If you could load the tape in, you could look at the resulting assembly and guess at an entry address, assuming you tied the start address down. As the other side of the tape suggests, they differ: 800 vs. 1f00. Hard to tell where the data is and where the code is without looking at it. If you made a hi-fi recording of it (44kHz) and played it for CiderPress: http://ciderpress.sourceforge.net , it could probably help make some inferences.

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Joined: Oct 11 2013
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Re: Of chickens and eggs

I realize this is re-opening a thread from about 8 years ago, but I got ahold of a photocopy of the relevant manual, and as of now at least it's scanned and here:

https://archive.org/details/sublogic-a2-3d1-animation-package-photocopy

Page 88 has the answers about where the programs load. 800.2FFFR is the load command, which puts the 3D code into memory at $800 and again at $1C00. The $1C00 copy is supposed to be at $6000, so it must be manually moved if you want to use that one. The main entry point is at $800 (or $6000), so you need to do some fiddling with HIMEM and LOMEM to use it in BASIC. Anyway, the manual is pretty thorough, and pretty indispensable.