Harry Potter Posted June 1, 2021 Share Posted June 1, 2021 Hi! I am working on MadLibAtari and need help with overlays. Upon start-up, it loads two stubs into Low RAM, which is what I call the beginning of RAM as used by the OS. I was wondering why the program was crashing as soon as a function in an overlay was called. I then added code to print out the load addresses of the two overlays, and they reported the wrong addresses. I am willing to share the files in question, but what can cause the error? How do I define the proper load addresses? Quote Link to comment Share on other sites More sharing options...
danwinslow Posted June 1, 2021 Share Posted June 1, 2021 (edited) Just guessing, but problems with low memory usually mean it's been written over by something, usually DOS. How low are you loading, and what DOS are you using? Extended ram is usually better for overlays, but it can limit the hardware types that can be used. Under the OS is also a decent option, but a lot of programs could conflict. Edited June 1, 2021 by danwinslow Quote Link to comment Share on other sites More sharing options...
Harry Potter Posted June 1, 2021 Author Share Posted June 1, 2021 I fixed the problem. I was using the tape buffer and some DUP.SYS code as targets for overlays. The problem was, for some reason, that the load functions were getting the wrong address. I had to supply the actual constants. I apparently can't rely on using the names of the constants. Now it works. Quote Link to comment Share on other sites More sharing options...
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